[tx-robot] updated from transifex
Remove duplicated object creation
Close notification in the status bar when a postcast ends
Remove unused import
Remove not null check on 'this' (not null by definition)
Simplify the sort per last modification date of old files
Adding bytes and Mbytes is wrong

file.length() returns size as byte, therefore keeping the variable size
as MByte and computing "size -= file.length()" is incorrect.
Wrong calculation of the current cache size during its purge

File.delete() returns 0 on a deleted file: the 'size' variable would
never descrease.
[NOT FOR MASTER] Remove build generated files
[NOT FOR MASTER] Use a released version of Showcaseview

- Remove the git submodule
- Update minimun sdk version to 11 (ShowcaseView minimal version)
[NOT FOR MASTER] Build with gradle 2.2.1

This version of gradle is required with Android Studio 1.x