Since bli_threads.h now includes pthreads directly, we need to had instructions in SConscripts everywhere for proper include path.
Frankly, I feel like this should be done in a global manner and not in a per lib fashion, but that is for another day.
This commit also fixes more missing properties
Editors Modules
* render/ module added in editors, moved the preview render code there and
also shading related operators.
* physics/ module made more consistent with other modules. renaming files,
making a single physics_ops.c for operators and keymaps. Also move all
particle related operators here now.
* space_buttons/ now should have only operators relevant to the buttons
specificially.
Updates & Notifiers
* Material/Texture/World/Lamp can now be passed to DAG_id_flush_update,
which will go back to a callback in editors. Eventually these should
be in the depsgraph itself, but for now this gives a unified call for
doing updates.
* GLSL materials are now refreshed on changes. There's still various
cases missing,
* Preview icons now hook into this system, solving various update cases
that were missed before.
* Also fixes issue in my last commit, where some preview would not render,
problem is avoided in the new system.
Icon Rendering
* On systems with support for non-power of two textures, an OpenGL texture
is now used instead of glDrawPixels. This avoids problems with icons get
clipped on region borders. On my Linux desktop, this gives an 1.1x speedup,
and on my Mac laptop a 2.3x speedup overall in redrawing the full window,
with the default setup. The glDrawPixels implementation on Mac seems to
have a lot of overhread.
* Preview icons are now drawn using proper premul alpha, and never faded so
you can see them clearly.
* Also tried to fix issue with texture node preview rendering, globals can't
be used with threads reliably.
