Objective:
* Make all text inputs have the ability to be "pending", not just ones
with a special mixin
Changes:
* Delete pending input widget
* Move pending input widget implementation to text input widget
* Update all uses of pending input widget
* Make pending image a reusable "texture"
* Update styles of text input widget for pending state
* Get rid of checking for mixin since all text inputs can be pending now
Bonus:
* Get rid of unused images, including .psd and .ai files
* Add transparency texture
* Fix input widget not using documented config value
* Fix documentation in select widget (lies!)
Change-Id: Ib46ab01dc39d706e5c25fd473dee0edce51b7e44
