[ticket/12930] core.ucp_pm_compose_compose_pm_quotepost_query_after

Adding the core.ucp_pm_compose_compose_pm_quotepost_query_after
event to ucp backend.

PHPBB3-12930
[ticket/12929] core.ucp_pm_compose_compose_pm_basic_info_query_before

Adding the core.ucp_pm_compose_compose_pm_basic_info_query_before
event to mcp backend.

PHPBB3-12929
[ticket/12929] Update to RC4

PHPBB3-12929
[ticket/12930] Update to RC4

PHPBB3-12930
[ticket/12929] Adding more variables to event.

More variables added that may be useful to events at this stage.

PHPBB3-12929
[ticket/12930] Adding more variables to the event

More variables, according to comments, were added to the event.

PHPBB3-12930
[ticket/12408] Add quick setting for "default guest style" to ACP

PHPBB3-12408
[ticket/12408] Simplified queries

PHPBB3-12408
[ticket/12408] Code cleanup

Rebased to see if travis will finally play along

PHPBB3-12408
[ticket/12408] Public functions and updated doc block

PHPBB3-12408
[ticket/12408] Changed lang vars, added fieldset and removed "default"

PHPBB3-12408
[ticket/12408] Clarify the behavior of "override style"

PHPBB3-12408
[ticket/12408] Fix white-space sniffer

PHPBB3-12408
[ticket/12929] Fixing event comment block and variable

PHPBB3-12929
[ticket/12930] Fixing event comment block and variable

According to comments on pull request

PHPBB3-12930
[ticket/13077] Move extension module to the top of the Customise tab

PHPBB3-13077
[ticket/12930] BUMP to RC5

PHPBB3-12930
[ticket/12929] BUMP to RC5

PHPBB3-12929
[ticket/12987] Cleanup the services.yml file

PHPBB3-12987
[ticket/13025] Add button template events

PHPBB3-13025