Added unit test that verifies removal of + at beginning of branch name
Added unit test that verifies removal of + at beginning of branch name

Starting a branch name with + has been blocked because it generated fatal errors. This verifies that + will be removed from the beginning of the name during sanitization.

artivilla/desktop,kactus-io/kactus,shiftkey/desktop,kactus-io/kactus,j-f1/forked-desktop,say25/desktop,j-f1/forked-desktop,artivilla/desktop,desktop/desktop,say25/desktop,j-f1/forked-desktop,shiftkey/desktop,desktop/desktop,desktop/desktop,kactus-io/kactus,say25/desktop,say25/desktop,kactus-io/kactus,shiftkey/desktop,artivilla/desktop,desktop/desktop,shiftkey/desktop,j-f1/forked-desktop,artivilla/desktop