[geary/wip/remote-retry] (10 commits) ...More refinements, progress

[Jim Nelson <jnelson src gnome org>]

Summary of changes:

  b0de536... Guard against length-0 blockquotes in html_to_flowed_text (*)
  4b644cc... Allow only a single inline composer at a time (*)
  a3aa8f7... Prioritize adding quote over changing reply type (*)
  6b4d841... Deal with MailboxAddresses, not strings, in composer (*)
  2d1d2ed... Allow quotes from multiple messages in a single reply (*)
  526f6e7... Paned composer for handling multi-replies (*)
  4ea2047... Merge branch 'master' into wip/cx-reestablish (*)
  22097a0... Prevent concurrent open and closes of remote folder (*)
  66dfb9b... Merge branch 'wip/cx-reestablish' into wip/remote-retry
  f368351... More refinements, progress

(*) This commit already existed in another branch; no separate mail sent