NOTE: BLI_winstuff.h was meant to be a wrapper around windows.h to handle
undefining various crap that windows.h defines. Platform specific headers
should only have to be included in a few places. This reduces the number
of inclusions of BLI_winstuff.h to 16 which is a much more reasonable
number (than the 144 or whatever it used to be)
To use; press the (temporal) icon in header. Switching widget types is by
pressing G, R or S once, if current widget type is different it switches,
otherwise it goes to normal Transform().
Widgets need a bit test for picking accuracy, correct drawing etc.
The rotate widget has a center button for 'trackball' rotate. That latter
can also be used for hotkey-based rotate.
In current code, all widgets remain in "Global" space, also in editmode.
Also widget updates while using normal transform has to be done.
2 Bugfixes:
- rotate in PoseMode had error for 2d 'around' center
- transform in postemode could crash, due to typo (& or |)
