Updated Greek Translation

Updated translation and added link to my profile on XDA (http://forum.xda-developers.com/member.php?u=4849551)
Update strings.xml

New string translated.
Fix some mistakes. (typing mistakes. lol)
French translation
Added Korean translations!

Firstly added Korean translations!
Add Android Studio related files to .gitignore
Allow excluding app from recents screen
Use tabs consistently
Add a flag instead of replacing existing flags
Allow forcing or preventing the app from being added to recents
Hook ActivityRecord's constructor instead, as it was overriding our settings sometimes
no message
Check if aInfo is null
Added licensing for the project (Apache v2)
Remove implementation of IXposedHookCmdInit, which is not needed
Enforce hiding the navigation bar in immersive mode

The new immersive mode in Android 4.4 is quite buggy. Even when the sticky
flag is set, the navigation bar is shown again after certain events (e.g.
when the window focus changes, the volume panel or keyboard is shown, ...)

This is not a problem of App Settings, many apps have to work around this.
The workaround in this commit ensures that the SYSTEM_UI_FLAG_HIDE_NAVIGATION
flag is always set, just before the app's SystemUI visibility is updated.

The navigation bar still pops up for a fraction of a second when opening
popup dialogs. Not sure if that can be resolved later, but it's acceptable
for now.

Fixes #24.
Update strings.xml
Merge pull request #24 from rovo89/immersive

Enforce hiding the navigation bar in immersive mode
Merge pull request #27 from Vagelis1608/master

Updated Greek Translation
Merge pull request #32 from jpeg729/french

French translation
Merge pull request #36 from Sanguinus112/master

German Translation