Fix T41228: Selection of bones bug.

Turns out to be mostly some cleanup in Pose select code, got rid of magic numbers
(now understand usual SEL_xxx enums) in ED_pose_deselectall(), which was renamed
to ED_pose_de_selectall, and have a new bool parameter to ignore visibility status
in its process (was the root of the reported issue).

Also factorized slightly "(de)select all" code. Yet this area could use much more
cleanup probably...
Fix T41223: F-Curve sliders won't update values during playback when mouse cursor is outside the left panel.
OSX/cmake: fix linking utf-functions if llvm is disabled
OSX/buildbot: after recent scons fix,  UTF lib linkage is handled dependent on config, so remove now obsolete lines
GHash: generic comparison for int[4]
BLI_listbase: consistent name prefix
missed last commit
Bugfix T41240: Home key doesn't show everything on F-Curves

Own copy and paste typo in 73d157e meant that this was not in some cases,
the bounds calculated may be incorrect.
BMesh: callback for bmbvh so caller can choose faces
Automatic commit by arc
leanup: style, use 'const' where possible, and simplified blend funcs.

Much better to use small loops when doing complex operations over color elements
(any serious compiler will flatten them anyway), avoids (some!) stupid mistakes when
editing their code.

Also, use min/max funcs instead of lengthier 'if (foo < 0) foo = 0'.
Cleanup: general cleanup in BLI_math code (mostly, use 'const' where possible, true/false for booleans, format for float litterals).
Fix addon crash when trying listdir a directory we have no permission to.
Code cleanup, make pie-menus code be closer to master