917639 - cli - fix changeset update add_repo command

It appears tha the ordering of the arguments to add_repo
may have been altered during a merge.  This fixes it so that
the user may now execute the following:

changeset update --from_product product --add_repo "repo 1"
   --org ACME_Corporation --name cs --environment dev
Merge pull request #1706 from bbuckingham/fork-917639

917639 - cli - fix changeset update add_repo command