fix for 2 errors introduced since release
- shape key NULL pointer dereference.
- use uninitialized variable for bmesh free.

also update credits and merge dissolve flag assignment. 


git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@56609 954f8c5b-7b00-dc11-b283-0030488c597c