Getting Python system paths for CEDET

[David Engster]

CEDET's Python support has a function
`semantic-python-get-system-include-path' which calls Python to more or
less simply do

import sys
print(sys.path)

and parse the resulting output. This little thing however has caused so
much problems in the past that I'd like to settle this thing now once
and for all.

I'm currently trying to get rid of the warning messages when compiling
our Python support since we're using stuff like `python-proc',
`python-buffer', `python-preoutput-result' and so on. I now see in
Emacs' python.el that there are new variables
`python-shell-internal-buffer', but the doc-string says that they are
only there because of CEDET compatibility. So it seems we're doing
things the wrong way.

So here's my question: What is The Right Way to send and parse the
command above? It'd be great if this could be made compatible with
'python-mode', which apparently is another Python mode for Emacs people
are using. Also, it should run with no problems in batch-mode so that
our unit tests run (this was a problem in the past).

-David