[ticket/11747] Add $phpbb_dispatcher to global

PHPBB3-11747
[ticket/11747] ucp_prefs_personal core events

PHPBB3-11747
[ticket/11747] ucp_prefs_personal template events

PHPBB3-11747
[ticket/11747] ucp_prefs_view core events

PHPBB3-11747
[ticket/11747] ucp_prefs_view template events

PHPBB3-11747
[ticket/11747] ucp_prefs_post core events

PHPBB3-11747
[ticket/11747] ucp_prefs_post template events

PHPBB3-11747
[ticket/11747] Use _prepend and _append for template events

PHPBB3-11747
[ticket/11747] Tweak some of the wording in the events doc

PHPBB3-11747
Merge pull request #1618 from VSEphpbb/ticket/11747

[ticket/11747] UCP Prefs Core and Template Events