MDL-47465 tool_monitor: add a new column to subs
MDL-47465 tool_monitor: Ignore used events

An event that has already contributed to a notification should not contribute to another notification for the same subscription.
This needs to be done so we do not overwhelm the user.
Merge branch 'MDL-47465-master' of git://github.com/ankitagarwal/moodle
MDL-47893 gradebook: Progress bar and continues for grade saving.

When you save a grade you are notified of how many grades have
been updated and any warnings.
MDL-47893 gradebook: Fixes for progress bar and output.

Outputs how many grades were updated.
Fixed grade overrides occasionally not working.
Updated behats.