Implement -exec-jump

[Eli Zaretskii]

> From: Vladimir Prus <vladimir@codesourcery.com>
> Date: Wed, 8 Apr 2009 09:50:16 +0400
> 
> 
> This patch, committed, implements the -exec-jump MI command.
> (Documentation follows later)

Please don't commit patches without the docs to go with them.  Many
people (and even distributions) use development snapshots or the CVS
directly these days, and I would like to avoid the situation where
they get features without documentation.  I think we all should want
this.

It is okay to _post_ a patch for review saying that the documentation
patch will be _posted_ later, but actually _committing_ the code part
is something very different.

Thanks.