Code cleanup / Sequencer:
* Remove "use_frame_blend" from RNA and UI file, not used anywhere in the code, also mark SEQ_SPEED_BLEND as deprecated. 

git-svn-id: https://svn.blender.org/svnroot/bf-blender/trunk/blender@55656 954f8c5b-7b00-dc11-b283-0030488c597c