Merge branch 'sp/maint-describe-tiebreak-with-tagger-date'

* sp/maint-describe-tiebreak-with-tagger-date: describe: Break annotated tag ties by tagger date tag.c: Parse tagger date (if present) tag.c: Refactor parse_tag_buffer to be saner to program tag.h: Remove unused signature field tag.c: Correct indentation