Reports sync failed notification.
Error detection
Show and hide sync notification correctly.
Change LoadReady event logic and animation logic.
sort usings.
Reload fragment when has had an error.
Replace ReloadCurrent with frag.ReloadData.
Merge pull request #439 from toggl/taavirehemagi-android-syncnotif

Displays bar with error message and a retry button when sync fails.
Closes #376

Conflicts:
	Joey/UI/Fragments/ReportsPagerFragment.cs