[ticket/11420] Fix notification options conversion

PHPBB3-11420
[ticket/11420] Forgot to include mock sql_insert_buffer

PHPBB3-11420
[ticket/11420] Rename migrations file to something more helpful

PHPBB3-11420
[ticket/11420] Fix comments, license link

PHPBB3-11420
[ticket/11420] Use !==, === when comparing strings

PHPBB3-11420
[ticket/11420] Fix tests

PHPBB3-11420
[ticket/11420] Fix tests

PHPBB3-11420
[ticket/11420] Fix tests

PHPBB3-11420
Merge remote-tracking branch 'EXreaction/ticket/11420' into develop

* EXreaction/ticket/11420:
  [ticket/11420] Fix tests
  [ticket/11420] Fix tests
  [ticket/11420] Fix tests
  [ticket/11420] Use !==, === when comparing strings
  [ticket/11420] Fix comments, license link
  [ticket/11420] Rename migrations file to something more helpful
  [ticket/11420] Forgot to include mock sql_insert_buffer
  [ticket/11420] Fix notification options conversion