commit: pay attention to submodule.$name.ignore in .gitmodules
"git status" does not list a submodule with uncommitted working tree
files as modified when "submodule.$name.ignore" is set to "dirty" in
in-tree ".gitmodules" file. Both status and commit honor the setting
in $GIT_DIR/config, but "commit" does not pick it up from .gitmodules,
which is inconsistent.
Teach "git commit" to pay attention to the setting in .gitmodules as
well.
Signed-off-by: Orgad Shaneh <orgads@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>