Removed hardcoded upstream in fabfile.utils.git.new_branch.
Removed hardcoded upstream in fabfile.utils.git.new_branch.

nathanielparke/huxley,bmun/huxley,bmun/huxley,bmun/huxley,ctmunwebmaster/huxley,ctmunwebmaster/huxley,ctmunwebmaster/huxley,nathanielparke/huxley,nathanielparke/huxley,nathanielparke/huxley,ctmunwebmaster/huxley,bmun/huxley