Merge branch 'jc/commit-unedited-template' into maint

When "git commit --template F" errors out because the user did not touch the message, it claimed that it aborts due to "empty message", which was utterly wrong. By Junio C Hamano (4) and Adam Monsen (1) * jc/commit-unedited-template: Documentation/git-commit: rephrase the "initial-ness" of templates git-commit.txt: clarify -t requires editing message commit: rephrase the error when user did not touch templated log message commit: do not trigger bogus "has templated message edited" check t7501: test the right kind of breakage