Blender Git Loki

More API reorganization

WIP commit, basically introducing a few things here:

* highlighted vs active widget.

Active widget takes all input and basically highjacks drawing of all
other widgets in the widgetmap.

* operator names for widgets. Now widgets will spawn operators based on
names that are passed on them. They will also modify a named property of
the operator and pass it on, after which operator can process it.

Manipulator:

* Fix error in plane manipulator handling.
* Don't show manipulator widgets on paint modes.

Only detect active widget on mousemoves. Now handler operates on
mouseclick (bound to change)

Merge branch 'master' into wiggly-widgets

Ring widgets:

Add a clipping style, just like manipulator

Undo previous changes to sound.

The sound system really needs better design for the sequencer and
patching it up now won't really help us in the long run.

Also the sequencer kept leaking file descriptors when preserving
the audio handlles on undo making the branch unusable on mac and
windows.

It's almost certain patching over this will lead to more trouble, better
handle it separately and keep the system working for now.

Kept threaded loading of waveforms since we control the file input
directly there and leads to nice speedup, but we still clear the whole
sound + the waveform on undo, which is pretty bad.

Merge branch 'master' into terrible_consequencer

Add space for facegroup storage

Widgets:

* Move lamp operators to a proper place
* Store a list of widgets to avoid polling too many times
* Fix wrong indices when widgetgroup was not used.
* Lamp widget now uses an arrow widget. This will be refined to make a
nice prototype for operator/widget interaction.

Use a property to make the transform operator widget driven.

Design is still pending here, but for now just use to not remove widget
display.

Change dial to something that resembles current rotation widget better.

Merge branch 'master' into hair_immediate_fixes

Conflicts:
source/blender/blenloader/intern/versioning_270.c

Merge branch 'master' into hair_immediate_fixes

Merge branch 'master' into gooseberry

Dial widget, used in rotation manipulator code.

The widget can still change in the future, also widget styles can always
be used to create new widget visualizations.

Implement non-3D drawing per widget.

Basically, 3D widgets stay the same size whatever the zoom is in 3D
view. Ported over from manipulator code.

Merge branch 'master' into wiggly-widgets

Switched back to blender implicit solver for merge.

Unified the main Eigen solver function a bit for constrained/unconstrained
solver variants.