Add Shift+Print keybinding to trigger 'mate-screenshot --area' for
interactive area selection. This gives users a dedicated keybinding for
area screenshots in addition to the existing Print (screen) and
Alt+Print (window) shortcuts.

Fixes mate-desktop/marco#157

This prevents race conditions with applications like mate-screenshot
that need to grab input (e.g. for area selection).

Fixes mate-desktop/mate-utils#37

Adds GNOME3-style dynamic workspace management. Workspaces are created
when no empty ones exist and removed when multiple empty workspaces are
present, maintaining exactly one empty workspace at the end.

Fixes #406

Adds support for configurable mouse actions on window titlebars,
including middle-click and scroll wheel events.

New actions added:
- close: Close the window
- raise: Raise window to top
- toggle_stick: Toggle sticky state (all workspaces)
- toggle_above: Toggle always-on-top state

Fixes #425
Fixes #787

Note: requries matching mate-control-center changes to work properly

find . \( -name '*.h' -o -name '*.c' \) -exec sed -i 'N;/^\n$/D;P;D;' {} \;

find . \( -name '*.h' -o -name '*.c' \) -exec sed -i 's/[[:space:]]*$//' {} \;
find . \( -name '*.h' -o -name '*.c' \) -exec sed -i 's/\t*$//' {} \;

Adding a new option to allow tile size cycling. When enabled, using the
keyboard shortcut for tiling multiple times in a row cycles the window
through different sizes (1/2 -> 1/3 -> 1/4 -> 3/4 -> 2/3 -> Untiled).