[Android] URBNG-350: ABCD answer fragment functionality
[Android] URBNG-350: Made some changes.
Notifications cleanup.

Cleaned notification packages, removed unnecessary files, little fixes
and changes.
Notification skeleton

Created basic functionality for notifications.
[Android] URBNG-350: Added progress dialog
Merge branch 'android' of github.com:blstream/UrbanGame into android
Remove equal signs generated by merge from strings file
Notifications mechanism completed

- Sub-task URBNG-361, URBNG-362 and URBNG-364 completed
- NotificationDiff sekeleton created
Merge remote-tracking branch 'upstream/android' into android
[Android] URBNG-350: Added parcelable objects from GPS pull request. Fixed some bugs.
Merge branch 'android' of github.com:blstream/UrbanGame into android
Bug fixed
Pull-request fixes after remarks
Merge remote-tracking branch 'upstream/android' into android
Merge branch 'android' of github.com:blstream/UrbanGame into android
[Android] URBNG-350: Deleted duplicates from strings.xml
Added comments
database update to provide hasChanges for user's game entity
Merge pull request #87 from element31/android

[Android] URBNG-350: ABCD answer fragment functionality
Merge pull request #92 from KamilLelonek/android

[Android] Notifications completed