update years in copyright notices

Signed-off-by: Christoph Lohmann <20h@r-36.net>
Applying the client sel handling of quinq.

When after unmanaging the the last selected client was unmanaged, select the
last client.
The check for a minimal new lastsel is not needed anymore.
Simplifying the lastsel handling a bit.

Some checks and comments were removed to simplify the function.
support urgency wm hints

Signed-off-by: Christoph Lohmann <20h@r-36.net>
add urgent color cmdline options

Signed-off-by: Christoph Lohmann <20h@r-36.net>