* jc/name-branch:
Don't permit ref/branch names to end with ".lock"
check_ref_format(): tighten refname rules
strbuf_check_branch_ref(): a helper to check a refname for a branch
Fix branch -m @{-1} newname
check-ref-format --branch: give Porcelain a way to grok branch shorthand
strbuf_branchname(): a wrapper for branch name shorthands
Rename interpret/substitute nth_last_branch functions