add frontend/kernel communication diagram to docs

Fix broken link and remove spurious copy of file with wrong extension

Add Git workflow docs from Gitwash. These are auto-generated docs from the gitwash template. To improve anything in the gitwash/ directory, please go instead to that project and make your improvements upstream: http://github.com/matthew-brett/gitwash

Added zmq kernel file which I forgot

Added files from our zmq prototype into main ipython tree. Currently added unmodified.

Small fixes so release builds.

Small updates for git-based release.

Ensure wxipython runs even if wx 2.6 is present. See https://bugs.launchpad.net/ubuntu/+source/wxbanker/+bug/394394 for a similar report

added optional taskids argument to TaskClient.clear() This fix was backported from Min's commit to trunk with minimal changes.

Adding .gitignore and updating release to remove bzr tag.