refactor for runCandidatesChain; also run outCandidates
new constants, hop-type; refactoring to help support form-submissions
retain offsets of discovered FORMs to aid later processing
extract HTMLForm INPUT details
per (overlay) settings, spawn high-priority POST when appropriate; annotate/add-headers to describe
when POST/submit-data requested, alter request method accordingly
when found in CrawlURI, add WARC-Simple-Form-Province-Status header
Merge branch 'simple_logins' into HER-2031
checkpoint support
comment-out debug output
Merge branch 'master' into HER-2031
fix failing ContentDigestHistoryTest