Fix python installation in comedilib-9999.ebuild.

Also:
* Install demo code when `doc` USE flag is set.
* Don't install comedi_calibrate man page, since we don't install a
  comedi_calibrate binary.

Bump to sci-libs/comedilib-9999 and add sci-misc/comedi-headers-9999.

The tricky part is handling /usr/include/comedi.h, which is supplied
by:

* the kernel's staging comedi drivers (but not installed)
    drivers/staging/comedi/comedi.h
* the Comedi module (installed via sci-misc/comedi-headers):
    include/linux/comedi.h
* the Comedilib module (not installed)
    include/comedi.h

The current CSV sources are very similar, but there are reasonable
differences with the staging version.  Hopefully everything works out
;).

The dependency setup is based on media-libs/alsa-lib and
media-sound/alsa-headers, which have to deal with a similar setup (in
kernal driver, out of kernal driver, and userspace library).

Added A. Griffis' CVS-based comedilib-0.7.22.ebuild.

From
  http://www.gentoo-wiki.info/HOWTO_RTAI_and_COMEDI_on_2.6_Kernel

Updated SRC_URI in comedilib-0.7.21.ebuild.

Added sci-libs/comedilib.

From
  http://sources.gentoo.org/cgi-bin/viewvc.cgi/gentoo-x86/sci-libs/comedilib/?hideattic=0
which was removed from the Portage tree in 2006.