SVN maintenance.

Add input sample averaging to PaintStroke.

Averages input samples to make the brush stroke smoother. Only mouse
location is averaged right now, not pressure/tilt/etc.

The DNA is in struct Paint.num_input_samples, RNA is
Paint.input_samples. In combination with PaintStroke usage this change
applies to sculpt, vpaint, and wpaint.

The range of useful values varies quite a bit depending on input
device; mouse needs higher values to match tablet pen, so set max
samples pretty high (64).

Release note section:
http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.64/Sculpting#Input_Stroke_Averaging

fix for
[#31502] Defocus max radius help tekst

Missing RNA_def_property_update functions for RenderSettings bake properties

Fix for [#31413] Code review testing: Regarding chunksize, could the
tooltip be made more clear

UI mafia fix thanks to venomgfx for reporting
* Color correction node

Fix for
[#31408] Code review testing: Button labels are invisible in many nodes

Fix for [#31418] Code review: OpenCL initialization
* Moved OpenCL initialization to first use
* cleaned up build files
* display some debug lines only when debugging is enabled.

[#31410] Code review testing: The color correction node in particular is
quite problematic in button layout
* Added first column with labels
* increased max size of node
* moved the start/end midtones to the bottom of the node

Fix for [#31367] render.drawLine not 2D filter aware:

The lines from render.drawLine() are now drawn before motion blur and 2D Filters.