qml: Add DropShadow to the OptionSwitch indicatorButton

- This commit is a follow-up to PR#101
(c026a3e).
- This addresses the suggestions given on this PR after it was merged.
- This commit also adds the DropShadow for the OptionSwitch's indicatorButton, as per the official design scheme of the project.

Author: shaavan

src/qml/components/ConnectionSettings.qml

@@ -11,25 +11,25 @@ ColumnLayout {
     spacing: 20
     Setting {
         Layout.fillWidth: true
-        header: "Use cellular data"
+        header: qsTr("Use cellular data")
     }
     Setting {
         Layout.fillWidth: true
-        header: "Daily upload limit"
+        header: qsTr("Daily upload limit")
     }
     Setting {
         Layout.fillWidth: true
-        header: "Connection limit"
+        header: qsTr("Connection limit")
     }
     Setting {
         Layout.fillWidth: true
-        header: "Listening enabled"
-        description: "Reduces data usage."
+        header: qsTr("Listening enabled")
+        description: qsTr("Reduces data usage.")
     }
     Setting {
         last: true
         Layout.fillWidth: true
-        header: "Blocks Only"
-        description: "Do not transfer unconfirmed transactions. Also disabled listening."
+        header: qsTr("Blocks Only")
+        description: qsTr("Do not transfer unconfirmed transactions. Also disabled listening.")
     }
 }

src/qml/controls/OptionSwitch.qml

@@ -4,14 +4,15 @@
 
 import QtQuick 2.15
 import QtQuick.Controls 2.15
+import QtGraphicalEffects 1.15
 
 Switch {
     id: root
     indicator: Rectangle {
         implicitWidth: 45
         implicitHeight: 28
         x: root.leftPadding
-        y: parent.height / 2 - height / 2
+        y: Math.round((parent.height - height) / 2)
         radius: 18
         color: root.checked ? "#F7931A" : "#DDDDDD"
         Rectangle {
@@ -23,5 +24,16 @@ Switch {
             radius: 18
             color: "#ffffff"
         }
+
+        DropShadow {
+            anchors.fill: indicatorButton
+            horizontalOffset: 0
+            verticalOffset: 5
+            radius: 10.0
+            spread: 0.0
+            samples: 21
+            color: "#00000040"
+            source: indicatorButton
+        }
     }
 }

src/qml/controls/Setting.qml

@@ -8,8 +8,8 @@ import QtQuick.Layouts 1.15
 
 Control {
     id: root
-    property bool last: false
-    property string header
+    property bool last: parent && root === parent.children[parent.children.length - 1]
+    required property string header
     property string description
     contentItem: GridLayout {
         columns: 2