v0.12.0-rc3

Changes in synapse v0.12.0-rc3 (2015-12-23)

• Allow guest accounts access to /sync (PR #455)
• Allow filters to include/exclude rooms at the room level
  rather than just from the components of the sync for each
  room. (PR #454)
• Include urls for room avatars in the response to /publicRooms (PR #453)
• Don't set a identicon as the avatar for a user when they register (PR #450)
• Add a display_name to third-party invites (PR #449)
• Send more information to the identity server for third-party invites so that
  it can send richer messages to the invitee (PR #446)
• Cache the responses to /intialSync for 5 minutes. If a client
  retries a request to /initialSync before the a response was computed
  to the first request then the same response is used for both requests
  (PR #457)
• Fix a bug where synapse would always request the signing keys of
  remote servers even when the key was cached locally (PR #452)
• Fix 500 when pagination search results (PR #447)
• Fix a bug where synapse was leaking raw email address in third-party invites
  (PR #448)