Improve performance by using a hash table or a faster approach
for looking up ids. Currently an automatic "move-to-front-when-accessed"
mechanism is implemented.

Output more information in /proc/fusion.

Improve performance (especially message throughput) by avoiding kmalloc.

Implement defering/blocking of SIGSTOP while a Skirmish is locked
by the process. This will avoid rare deadlocks when pressing Ctrl-Z
in the terminal where a DirectFB slave application has been started.

Revert semaphores to spinlocks where possible.

Implement user space based skirmish_prevail()/dismiss() for the
uncontended case, similar to futexes.

Fix types.
