final refactoring before shipping 1.2.3 version

Merge remote-tracking branch 'origin/master'

bug on the pause feature fix #1

- fixed a bug causing the file to be corrupted on the server.
- some refactoring

several changes

- fixed a bug in which the program was accepting thumbs whose names were not according with the episode name
- added support for pause/stop upload
- changed the way the .cfg file was handled
- changed and added some documentation

some optimazation

- Optimized the way in which the upload list is updated
- Other minor changes

Massive amount of changes

- Functionality implementation of individually add or remove an episode in the episode selected list
- Several changes in the way the screen is managed
- Optimized way to check if all selected files has an .cfg entry
- Halfway through implementing a way to add episodes while others are being uploaded
- There are colors in the upload list now
- More information about the file being uploaded
- Preparing for implementing stop and pause upload

Several changes

- Added some documentation
- Now the program handles errors in the .cfg file
- Now the program handles if the episode was already registered in the database
- Now the program handles if the episode being uploaded is the last of the season

Added some important imports