Implementing spring-back version of reordering

-> If you hover above occupied cells, we try to find a new location
   for the items. The items only remain in the temporary position
   while the drag ivew is over their original position after which
   they animate back.
-> Items in the temporary positions animate in such a way so indicate
   that they are in a temporary state, and in such a way so as to hint
   at where they will return to.

Change-Id: I7537c65228c505afbd2f1c22938cfd9d7719839a
2 files changed