Combining gl branch option-c and -su should report an error

[chmike]

The instruction gl branch -c origin/test2 -su origin/test2 doesn't report an error, but only execute the gl branch -c origin/test2.

It would be handy to be able to create and set the upstream branch in one instruction like for instance gl branch -csu origin/test2.

[chmike]

Also when I tried gl branch -c test4 -c origin/test4 only the last -c origin/test4 was taken in account.
It should ideally report an error.

[spderosso]

255b6d4