Branch for preparing a 1.2.2 release

This release will be introducing new options for disabling the error
message that displays during automatic on-the-fly playback.
Introduce automatic_xxx_errors options

These new boolean options will allow the user to suppress the error
dialogs that appear during review.
Update documentation for configuration screen

Adds the "show errors" checkbox to the screenshot and explains what it
does.
Implement show_errors handling for reviewer

This adds flags and checks to suppress error messages if the user
chooses to opt out of them.
Additional documentation on manual playback

Adds a note to the playback configuration documentation page explaining
that manually-triggered playback will still display error messages.
Release of v1.2.2

Adds support for the user to toggle off the display of error messages
caused by on-the-fly automatic playback.

(Merge branch 'pre/v1.2.2' into stable)