Documentation: Enhance documentation (index, keywords)

* Add some keywords for the concept index.

* Add some keywords for the keystroke index.

* Mark invalid or unclear documentation with TODO.
  Is there a better proposal how to do this?

* Fix copy+paste error in ColdFire section
  (options were copied from ARM).

* Fix documentation for Wine.

* Add placeholders for missing system emulations.

* Add placeholders for missing user emulation commands.

* Add an appendix with license (to be discussed).

* Add an appendix for every type of index which is
  supported by texinfo. Currently, not all are used,
  but this might change in the future.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
