[[Split portion of a mixed commit.]]

Another fix to import image as plane, due to recent alpha refactor in blender code (thanks to meta-androcto for the report on IRC).

Never use a generator as enum's "items" value!

Yet there is some work to be done on the 'GRID' mode of lists, current layout code is stupid (and nearly unusable)...

Updated to use UI_UL_list as template_list (also a bunch of style cleanup, still some work to do here!).

add back bevel tool menu, it no longer crashes.

these crash blender instantly with no errors

update for api changes, note this script isnt using the API properly, it adds a draw handler but never removes it.

make addons blender versions consistent

disable initializing data on the scene when registering netrender. addons registration shouldnt modify the current blend file.

* Update for correct calculation of feet-inch (Patch by Alessandro Sala)
* Upped precision for display to 5 digits (same as Blender)

Grease pencil convertion to curves and their selection is now adapted to Blender 2.65, both for "Edit Strokes" and "Reorder Splines" features.

don't overwrite alpha with material `illum` setting, or when using an alpha texture- if its already been set.

added scale object on export, rebuild object on export, and check mesh for vertices's error mesh. update the menu to rework the layouts.

Some enhancement to how plane size is computed. Now you have three choices (absolute, to directly specify the result height, and dpi or dpbu [dots per Blender Unit], to use image definition). Based on an idea and code from mat ali, thanks!

Also fixed correct use of overriden context (not really a bug, but printed annoying warning messages in the console).

MHX importer: the idea to use rna props did not pan out, because it lead to errors when a saved blend file with an mh character was reloaded. Fixed that.