Bump to 1.6.1 and use version from submodule

Use the version from the submodule for the gem version. So it is
consistent with other types of toolkit packages.

Change the jenins.sh to update the version of the submodule as part of jenkins.sh and commit the updated submodule after the gem has been published. I can then update jenkins to push the master branch as a post build step.
@alext damn, hadn't thought of them. I have updated the jenkins.sh to ensure it only creates a new commit on version change and moved it before the gem publishing step. Does that look better?