doc: submodule.*.branch config is keyed by name
doc: submodule.*.branch config is keyed by name

Ever since 941987a5 (git-submodule: give submodules proper names,
2007-06-11) introduced the ability to move a submodule from one path
to another inside its superproject tree without losing its identity,
we should have consistently used submodule.<name>.* to access
settings related to the named submodule.

Signed-off-by: W. Trevor King <f75897670c17327c42ab201733fb8a81ff9f4c34@tremily.us>
Signed-off-by: Junio C Hamano <a6723cc3f76163bf7adb636a73ac3b0ceb3e6b9b@pobox.com>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git