Change edge loop select and edge ring select to be consistent with
other selection operators. Instead of having only a single "extend"
option which causes the selection to toggle, there are now
three options:
- extend: adds to selection
- deselect: removes from selection
- toggle: toggles the selection

The default keymap is adjusted to have identical behavior as before,
using these new options, so end-users shouldn't experience any
difference.

Modifications to the view3d.select() operator:

1. Two new boolean options have been added to the operator: "deselect"
and "toggle".
2. The previous behavior of "extend" (toggling the selection) has
been moved to the "toggle" option.
3. "extend" now only extends the selection, it never deselects.
4. "deselect" is pretty self-explanatory: it deselects (i.e. opposite
of extend).
5. The built-in keymap has been changed to use "toggle" where
"extend" was used before for this operator, to maintain the
previous behavior in the default keymap.

In short, this works towards making "extend" and "deselect" fully
consistent across all selection tools (adding to and removing from
selection, respectively), but still preserves the old behavior
as well.

(Patch reviewed by Brecht.)

Action constraint transform channel was listing X Scale as Z Scale,
resulting in two Z Scale listings in the menu. Fixed.

Button for adding shape keys now creates shapes from base mesh instead of
from the current shape mix. The old behavior is still accessable from the
menu as "New Shape From Mix".

Checked with Sergey and Bassam that this is a good change. New users
expect the add shape button to simply add a new blank shape, and get
confused when that is not the case. It is also really easy to
accidentally have other shape information in a new shape when the
"from mix" behavior is default.

Editbone length was still using "normalize()" instead of "normalized()"
for setting length, which was thus failing and erroring out.

Removed old rigify code, as it is starting to interfere with the newer Rigify addon.
The newer addon currently resides here: bzr://bzr.cessen.com/rigify
But will eventually be included in svn.

Fix for the eyelid rig type. Vector(#, #, #) to Vector((#, #, #))

Updated rigify scripts for minor driver api change.

Added tongue and neck rigs. The neck rig is quite solid, I think, and is working well in production on Durian. The tongue rig is a bit hacky, but I'm adding it for now since we're using it in Durian.
Also added pupil dilation to the eye rig type, and made the finger rig type work with two-digit fingers.

Made a more generic rig type for giving animators direct control over shape keys. With this rig type you can attach shape keys both to the transforms of the bone and any number custom properties on the bone.