"git submodule update" and "git submodule add" supported the
"--reference" option to borrow objects from a neighbouring local
repository like "git clone" does, but lacked the more recent
invention "--dissociate". Also "git submodule add" has been taught
to take the "--progress" option.
* cf/submodule-progress-dissociate:
submodule: add --dissociate option to add/update commands
submodule: add --progress option to add command
submodule: clean up substitutions in script
projects / thirdparty / git.git / commit
