Fix T37929: inherit scale for dupli faces was not shown greyed out when it should be.
Make makesdna capable of detecting 32bit alignment issues on 64bit platform

Summary: Just some extra comparison between native and 32bit structure length was needed.

Reviewers: brecht, campbellbarton

Reviewed By: brecht

Differential Revision: http://developer.blender.org/D131
CMake: attempt to fix Boost detection on Fedora 20, which omits -mt.
Move python threading stuff to own file in bf_python_ext

This way blender player can easily use BPY_thread_save/restore.
Not so much important for master branch, but crucial to solve
linking issues in threaded depsgraph branch.
UI: communicate external data autopack better in the UI.

Previously there was no way to see if autopack was enabled. Now the external
data menu has 3 entries instead of 2:

* Automatically Pack Into .blend (with checkbox to indicate autopack on/off)
* Pack All Into .blend
* Unpack All Into Files

Fixes T37608, includes modifications by Brecht from the original patch.

Reviewed By: brecht

Differential Revision: http://developer.blender.org/D118
Code Cleanup: style
Merge branch 'master' of http://git.blender.org/blender