Fix ClassCastException
Fix bug where second collapse is not animated
Merge pull request #9 from idunnololz/idunnololz/fix_second_time_collapse

Fix bug where second collapse is not animated
Merge pull request #10 from idunnololz/idunnololz/fix_crash_collapse_offscreen_item

Fix crash when collapsing item off screen
Merge pull request #13 from idunnololz/idunnololz/fix_class_cast_crash

Fix ClassCastException
Fix issue where collapse animation is really slow
Fix issue where last group does not collapse properly

There is an issue where the last group does not collapse properly if the AnimatedExpandableListView is inside a ViewGroup with the property WRAP_CONTENT as the layout width.