The user can now configure the following:
* Whether to prefer CSDs or SSDs. But note that this is only a hint to
the compositor - it may deny our request. Furthermore, not all
compositors implement the decoration manager protocol, meaning CSDs
will be used regardless of the user configuration (GNOME/mutter
being the most prominent one).
* Title bar size and color, including transparency
* Border size and color, including transparency
Also drop support for rendering the CSDs inside the main surface.
They where previously identical to the corresponding 'regular'
colors. Now, we've done a saturated add with 0x202020 (which seems to
be roughly the difference between the other regular and bright
colors).
