[geary] (13 commits) ...Merge branch 'wip/181-special-folder-dupes' into 'master'

[Michael Gratton <mjog src gnome org>]

Summary of changes:

  faf7a2b... Add some unit tests for Geary.ImapDb.Account folder managem (*)
  4fefda9... Remove unwanted debuging cruft (*)
  b0f85b3... Ensure accounts don't accidentially create multiple inbox-t (*)
  46bb4d1... Ensure MinimalFolder remote open forces closed on hard erro (*)
  41bb79d... Stop duplicate inboxes being created, not being listed (*)
  5a22e8e... Convert Geary.FolderRoot to be an actual root, not just a t (*)
  423a1dc... Add additional FolderPath unit tests (*)
  ddbe6e0... Revamp Geary.FolderPath implementation (*)
  e1fd9da... Fix pathological FolderPath.is_equal() case, add unit test (*)
  1ed0f5a... Fix ambiguous test in AccountInformation.set_special_folder (*)
  b1461d8... Add some useful debugging to GenericAcount (*)
  bb0060b... Rework GenericAccount::ensure_special_folder_asyc yet again (*)
  5152581... Merge branch 'wip/181-special-folder-dupes' into 'master'

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