Notable changes

• Improve original post discovery algorithm. https://github.com/snarfed/bridgy/issues/51
• Flickr tweaks. https://github.com/snarfed/bridgy/issues/466
• Add mf2, activitystreams, atom, and search to interactive UI. https://github.com/snarfed/granary/issues/31 https://github.com/snarfed/granary/issues/29
• Improved post type discovery (using mf2util).
• Extract user web site links from all fields in profile (e.g. description/bio).
• Add fabricated fragments to comment/like permalinks (e.g. #liked-by-user123) so that object urls are always unique (multiple silos).
• Improve formatting/whitespace support in create/preview (multiple silos).
• Google+:
  • Add search.
• Facebook:
  • Fetch more things in get_activities: photos, events, RSVPs.
  • Support person tags in create/preview.
  • Prevent facebook from automatically consolidating photo posts by uploading photos to "Timeline Photos" album.
  • Include title in create/preview.
  • Improve object id parsing/resolving.
  • Improve tag handling.
  • Bug fix for fetching nested comments.
  • Misc improvements, API error/flakiness handling.
• Flickr:
  • Create/preview support for photos, comments, favorites, tags, person tags, location.
• Twitter:
  • Create/preview support for location, multiple photos.
  • Fetch quote tweets.
  • Fetching user mentions improvements, bug fixes.
  • Fix embeds.
  • Misc AS conversion improvements.
• microformats2:
  • Improve like and repost rendering.
• Misc bug fixes.
• Set up CircleCI.