[geary/wip/ricotz/webkit] (34 commits) ...Clean up JS util API courtesy the new bindings.

[Rico Tzschichholz <ricotz src gnome org>]

Summary of changes:

  5d58f16... Update Appsteam metainfo to point to new help page. (*)
  057e733... Fix a crash saving an attachment with unknown content type. (*)
  598f1a5... Increase len of non-truncated strs that TestCase.assert_str (*)
  7a9960c... Fix crash if the login session's secret service has no pass (*)
  01a43bb... Fix ContentTypeTest.guess_type_from_buf occasionally failin (*)
  4251596... Support in-memory SQLite databases, as well as on-disk data (*)
  743b24d... Make database classes more amenable to asynchronous use. (*)
  587e4e7... Add TestCase.assert_null_string method. (*)
  6f7cff2... Move MidstreamConverter to same source file as other stream (*)
  5c73fbc... Push all ImapDB path management down into to ImapDb.Account (*)
  15d8789... Move attachment related code from ImapDB.Folder to Attachme (*)
  037af00... Improve how attachments are saved to the db and disk. (*)
  a2a9568... Support default content types for both displayed and attach (*)
  bfe665d... Add unit tests for Geary.RFC822.Message body content, fix a (*)
  f1c7976... Ensure we always use the one, same codepath when decoding t (*)
  40d9b77... Revert "Remove a number of redundant fns in Engine.Util.Asc (*)
  ba861b8... Fix failing RFC822.Mailbox test. (*)
  967e401... Replace custom and extern functions in Geary.Ascii with std (*)
  ffb4bef... Merge branch 'wip/795906-turkish-locale'. Fixes Bug 795906. (*)
  d91dd36... Update unit tests to ensure text attachments saved without  (*)
  f78939c... Push GResource URL for test data down so it's accessible to (*)
  43341cd... Merge branch 'wip/ricotz/webkit'. Fixes Bug 788113. (*)
  d4aaa3c... Bump library dependency min versions to reflect reality. (*)
  386f986... Revert "Merge branch 'wip/ricotz/webkit'. Fixes Bug 788113. (*)
  fe9461e... Add a unit test for upgrading an actual Geary v0.6 database (*)
  440a4d5... Merge branch 'wip/726281-text-attachment-crlf'. Fixes Bug 7 (*)
  65b44c3... Don't strip CRLF from iCal, vCard, and other formats that r (*)
  2b1f0e8... More dependency cleanup. (*)
  8d3b16c... Fix as many valac deprecation and valadoc unused warnings a (*)
  1b49fc1... Ensure Db.Database corruption check doesn't fail on missing (*)
  4ac7c10... Provide and use an async make_directory_with_parents in Db. (*)
  a6e81d8... bindings: Drop custom javascriptcore-4.0 and webkit2gtk-4.0
  ce4a5f9... Adjust to upstream javascriptcore-4.0 bindings
  6048b37... Clean up JS util API courtesy the new bindings.

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