RFC: add ability to "source" Python code

[Eli Zaretskii]

> From: Tom Tromey <elpa@tromey.com>
> Date: Sat, 07 Feb 2009 18:16:10 -0700
> 
> This patch adds Python support to the gdb "source" command.
> I added this after several user questions about how to do this.
> Also, due to completion, it is much more convenient than the
> equivalent "python" command.

Thanks.

> This could use a documentation review.

The documentation part is okay, except that I'd add a @cindex entry
there about sourcing Python code files.

However, I don't think I like the idea of GDB barfing if Python
support is not compiled in.  I think it should simply try to interpret
the file as GDB scripting commands.

I also think we need a NEWS entry for this feature.