* jc/maint-log-grep-all-match-1:
grep.c: make two symbols really file-scope static this time
t7810-grep: test --all-match with multiple --grep and --author options
t7810-grep: test interaction of multiple --grep and --author options
t7810-grep: test multiple --author with --all-match
t7810-grep: test multiple --grep with and without --all-match
t7810-grep: bring log --grep tests in common form
grep.c: mark private file-scope symbols as static
log: document use of multiple commit limiting options
log --grep/--author: honor --all-match honored for multiple --grep patterns
grep: show --debug output only once
grep: teach --debug option to dump the parse tree