Update ctrl+alt window management functionality.

* Use double-headed resize arrows instead of single headed.
* Remove border highlighting, it is replaced by mouse cursor.
* Don't enter drag state if window is not movable.
* Make Ctrl+LMB resize window border like RMB.
* Define other 3 corners in default decorator and resize by them
  as well
* Update mouse cursor to show arrows when over borders and control
  is held.
* Set the move cursor on ctrl+alt if the window is movable.
* Set cursor to not allowed on ctrl+alt if window is not movable.
* Set the cursor to appropriate resize arrow on ctrl+alt+RMB.
* Set the cursor to not allowed on ctrl+alt+RMB if not resizable.
* Make window go to back when you right-click or ctrl+click
  on the tab. It doesn't lose focus though unlike BeOS R5.
Look at resize flags when setting resize arrows
Fix gcc4 build by adding parens