Added fade-in effect to cards in index list
Changed animations to not depend on external libraries
Merge branch 'development' into index_step2
Generalization in slider handler. Not finished.
Added possibility to swipe away list items. Cannot undo for now.
Improved swipe animation to depend upon swipe velocity as well as
distance.
Fixed a crash that occured when the navigation was opened after swiping
cards. Also moved some code to the abstract list adapter class, in order
to make it easily available to other subclasses in other fragments.
Commented code a bit better.
Added a bunch of comments and Javadoc.

Added a bunch of comments and Javadoc.
Merge branch 'index_step2' into development