This reduces chances of errors where consumers of strings mutate inputs
and reduces memory usage of the app.
Test suite passes now, but there may be some stuff left, so we will run
a few sites on a branch prior to merging
* FEATURE: add branch option to remote theme import
* FIX: Add missing variable in params
* FIX: Add missing param for import_theme method
* SPEC: Add test methods for branch support in git import
* FIX: Add missing space to scss style
* Do not assume default branch as master
* Change branch field placeholder
* FIX: add missing div start tag
