Also fixes a bunch of comments, implementation based off of v-d.
Added isOnClipboard and setCutMode functions to LLInventoryClipboard, in part from v-d's LLClipboard.
LLInventoryFilter has a few rearrangements of code; only real change is now it has checkAgainstClipboard and uses it to filter out cut items.
There is a massive retabbed block in llinventorymodel.cpp, view without space changes. Implements removeObject.
Note: We are not afflicted by MAINT-1197: Fix inventory deselection/reselection when cutting items
