[geary] (12 commits) ...Merge branch 'wip/structured-logging' into 'mainline'

[Michael Gratton <mjog src gnome org>]

Summary of changes:

  f7c8332... Add Geary.Loggable interface for objects that can log and b (*)
  0bb530d... Add Geary.Logging.Flags.ALL to specify a message should alw (*)
  de8c385... Convert key classes to implement Loggable (*)
  b0ca8c9... Switch to using GLib structured logging (*)
  ff3c4b0... Fix incorrect log field key being used for Loggable objects (*)
  337ea2e... Integrate Logging.Record into structured logging system (*)
  258537e... Pretty-print well known logging variables (*)
  95e856b... Ensure logging system is thread-safe (*)
  a0d2e73... Add Geary.Logging.clear method, call it on app shutdown (*)
  e338d5d... Stop printing elapsed time between logs, log absolute ms in (*)
  6e07d06... Use a reasonable sized buffer when formatting log messages (*)
  7e91b7a... Merge branch 'wip/structured-logging' into 'mainline'

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