[geary/mainline] (22 commits) ...Merge branch 'wip/geary-inspector' into 'mainline'

[Michael Gratton <mjog src gnome org>]

Summary of changes:

  ac46174... Depend on libhandy for the client build (*)
  7f13ce4... Target Ubuntu and Fedora devel images in CI (*)
  4332155... Make generic account editor ListBoxRow style reusable elsew (*)
  93cb84b... Make runtime information collection reusable elsewhere (*)
  ae4d765... Add basic Geary Inspector, hook it up to Alt+Shift+I (*)
  0bac8f7... Keep a bounded list of last n log messages (*)
  1f4ef0a... Display all known logs in inspector (*)
  1b121e0... Update the UI when the switcher pane changes (*)
  0e4486b... Make Copy button copy selected log rows, make it less promi (*)
  b5f27dc... Add UI and implement saving details and logs to file (*)
  e5893e1... Implement filtering log messages (*)
  fc119eb... Add a means for apps to be notified as new log records are  (*)
  6dc8b27... Append new log records to the inspector and scroll to them (*)
  584ead9... Tidy up inspector tooltips (*)
  ccde37c... Enable pausing/unpausing the log viewer (*)
  d87a2b0... Enable some keyboard shortcuts for the inspector (*)
  993f7cc... Ensure there is only ever one Inspector open at a time (*)
  194ca0e... Blacklist displaying certain annoying messages in the Inspe (*)
  e428d7b... Minor code tidy up (*)
  9c5dc14... Use MainContext.invoke to handle appending new log messages (*)
  ae1e36e... Fine tune Inspector filtering (*)
  6234405... Merge branch 'wip/geary-inspector' into 'mainline'

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