2.5 Themes and general cleanup (#27)

* 2.5 THEMES folder adjustment

- ditched obsolete EdgeTX folder
- added files compatible with EdgeTX 2.5 theme switching

* Temporarily restore default background

* Remove auto-generated settings file

* Typos

Co-authored-by: Peter Feerick <peter.feerick@gmail.com>

sdcard/horus/THEMES/FM2M_Concrete.yml

@@ -0,0 +1,17 @@
+---
+summary:
+  name: FM2M Concrete
+  author: JimB40
+  info: Grays are sexi. Let's explore this bando.
+colors:
+ PRIMARY1:   0xA0A0A0
+ PRIMARY2:   0x202020
+ PRIMARY3:   0x505050
+ SECONDARY1: 0x808080
+ SECONDARY2: 0x505050
+ SECONDARY3: 0x303030
+ FOCUS:      0xC0C0C0
+ EDIT:       0xEEEEEE
+ ACTIVE:     0xD0D0D0
+ WARNING:    0x404040
+ DISABLED:   0x808080

sdcard/horus/THEMES/FM2M_Greenfields.yml

@@ -0,0 +1,17 @@
+---
+summary:
+  name: FM2M Greenfields
+  author: JimB40
+  info: Green grass, yellow sun and blue sky. This is summer time.
+colors:
+  PRIMARY1:   0x000000
+  PRIMARY2:   0xFFFFC0
+  PRIMARY3:   0x003000
+  SECONDARY1: 0x005000
+  SECONDARY2: 0x009900
+  SECONDARY3: 0x00C800
+  FOCUS:      0xFF8C00
+  EDIT:       0x6074FF
+  ACTIVE:     0xF7E400
+  WARNING:    0xE00000
+  DISABLED:   0x808080

sdcard/horus/THEMES/FM2M_HellYeah.yml

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+---
+summary:
+  name: FM2M Hell Yeah!
+  author: JimB40
+  info: Little devil inside my plane.
+colors:
+  PRIMARY1:   0x220000
+  PRIMARY2:   0xFF2222
+  PRIMARY3:   0x4F0000
+  SECONDARY1: 0x080000
+  SECONDARY2: 0xA00000
+  SECONDARY3: 0x770000
+  FOCUS:      0x080000
+  EDIT:       0x440000
+  ACTIVE:     0xFF8080
+  WARNING:    0xFFFFFF
+  DISABLED:   0x000000

sdcard/horus/THEMES/FM2M_Vineyard.yml

@@ -0,0 +1,17 @@
+---
+summary:
+  name: FM2M Vineyard
+  author: JimB40
+  info: For wine lovers. Remember. Don't drink and fly.
+colors:
+  PRIMARY1:   0x00DD00
+  PRIMARY2:   0xFFFF90
+  PRIMARY3:   0xA000A0
+  SECONDARY1: 0x780078
+  SECONDARY2: 0x006000
+  SECONDARY3: 0x400040
+  FOCUS:      0x008000
+  EDIT:       0x6060F0
+  ACTIVE:     0x004000
+  WARNING:    0xFFFFFF
+  DISABLED:   0x808080

sdcard/horus/THEMES/readme.txt

@@ -0,0 +1,148 @@
+!!! IMPORTANT
+EdgeTX 2.5 Theme implementation is first approach and may be changed in next
+releases. That means color variables and YAML file structure may change.
+
+
+EdgeTX 2.5 Theme
+----------------
+There are 11 EdgeTX OS color variables that are used to define EdgeTX UI look &
+feel. PRIMARY1, PRIMARY2, PRIMARY3, SECONDARY1, SECONDARY2, SECONDARY3, FOCUS,
+ACTIVE, WARNING & DISABLED.
+Color values format uses 24bit value (RGB color scheme) coded in hex format
+RRGGBB where RR stands for Red component value, GG for Green and BB for Blue.
+Each component can have 256 values (00-FF range in hex format)
+
+RGB color scheme examples:
+FF0000 (Light Red)
+440000 (Dark Red)
+00FF00 (Light Green)
+002400 (Dark Green)
+0000FF (Light Blue)
+000064 (Dark Blue)
+FFFFFF (White)
+808080 (50% Gray)
+202020 (Dark Gray)
+
+
+EdgeTX 2.5 Theme definition
+---------------------------
+Themes colors definition is stored in YAML format text files placed in /THEMES
+folder in radio's SD card. YAML (Yet Another Markup Language) is simple markup
+language to define data structure. It can be edited using any text editor.
+File name has to have .yml extension.
+Example: custom_theme.yml
+
+Additionally you can include graphic file (in PNG format) to display in EdgeTX
+User Interface Tab theme preview. To display preview file name must be the same
+as YAML file.
+Example:
+If theme color definition is name new_theme.yml graphic preview file must be
+named new_theme.png
+
+
+EdgeTX 2.5 Theme definition YAML file structure
+-----------------------------------------------
+Data in YAML file is structured using basic scheme "name: value"
+Leading spaces are important as they define data group assignment.
+
+Example of theme colors definition:
+
+---
+summary:
+  name: Theme name
+  author: Creator
+  info: Here is short description
+colors:
+ PRIMARY1:   0xA0A0A0
+ PRIMARY2:   0x202020
+ PRIMARY3:   0x505050
+ SECONDARY1: 0x808080
+ SECONDARY2: 0x505050
+ SECONDARY3: 0x303030
+ FOCUS:      0xC0C0C0
+ EDIT:       0xEEEEEE
+ ACTIVE:     0xD0D0D0
+ WARNING:    0x404040
+ DISABLED:   0x808080
+
+'---'         YAML format marker (must be placed as first line)
+'summary: '   Group marker (description)
+' name: '     Name of theme displayed in EdgeTX UI
+' author: '   Name of author displayed in EdgeTX UI
+' info: '     Short info about theme displayed in EdgeTX UI
+'colors: '    Group marker (colors definition)
+' PRIMARY1: ' ETX color variable in 0xRRGGBB format (0x means value is in hex)
+' PRIMARY2: ' ETX color variable in 0xRRGGBB format (0x means value is in hex)
+etc
+
+
+ETX 2.5 UI elements color variables assignment
+----------------------------------------------
+PRIMARY1
+ Label text
+ Button text (not focused)
+PRIMARY2
+  ETX Logo icon,
+  TopBar Icons
+  TopBar text
+  TopBar tab name text
+  BottomBar text
+  Editable field background
+  Editable field text (editing)
+  Button text (focused)
+  PopUp selectable field background
+  Trim knob
+  Slider knob
+PRIMARY3
+  Scroll marker
+  Inactive part of TopBar icons
+SECONDARY1
+  TopBar background
+  BottomBar background
+  Trim knob path
+  Trim Knob shadow
+  Slider path
+  Slider knob shadow
+SECONDARY2
+  Label background
+  Button background
+SECONDARY3
+  Main screen's background
+  PopUp's background
+FOCUS
+  ETX Logo background
+  TopBar icon background (selected)
+  Label background (focused)
+  Editable field background (focused)
+  Trim knob
+  Slider knob
+EDIT
+  Editable field background (editing)
+ACTIVE
+  Buttons background (button active)
+  Editable field background (variable active)
+WARNING
+  Label text (warning)
+DISABLED
+  Disabled elements
+
+
+Creating EdgeTX 2.5 theme color definition
+-------------------------------------------
+1. Create *.yml file with theme definition
+2. Create *.png file with theme preview
+3. Place *.yml & *.png files in /THEMES folder on radio's SD Card
+4. Reboot radio
+5. Navigate to 'User Interface' Tab in EdgeTX
+6. Select new theme from the dropdown list.
+
+
+EdgeTX 2.5 Theme implementation
+-------------------------------
+1. If there is no files in /THEMES folder default EdgeTX theme will be applied.
+2. selectedtheme.txt file holds name of selected theme YAML file. If empty or
+not present default EdgeTX theme will be applied.
+3. If color variable definition is omitted in YAML file, last applied color
+value is used (color value from previously used theme)
+4. If *.png file in not present or has different name than YAML file it won't be
+displayed in EdgeTX UI