Fix Deploying Mercurial by a Non Branch/Tag

Currently git deploys allow you to deploy by any valid identifier for a commit, however Mercurial deploys only allow deploying by branches or tags. This brings the two in line and now Mercurial users will no longer have to tag a commit just to deploy it.

This PR should support

    # Branches
    gondor deploy primary default

    # Tags
    gondor deploy primary v1.0

    # Local Revision Numbers
    gondor deploy primary 2

    # SHA Hashes
    gondor deploy primary f0deb90d5b80