[ticket/7580] Add test for IF {VAR} is defined in templates

http://tracker.phpbb.com/browse/PHPBB3-7580
This test demonstrates that is possible to test if a
variable exists and then use it if it does, similar to
using isset(), but in template/twig syntax.
<!— IF {VAR} is defined —>{VAR}<!— ENDIF —>

PHPBB3-7580
[ticket/12269] Delete folder mods in language

Deleted mods folder in phpbb/language/en/.

PHPBB3-12269
Merge branch 'ticket/12269' of github.com:netdeamon/phpbb into develop

# By netdeamon
# Via netdeamon
* 'ticket/12269' of github.com:netdeamon/phpbb:
  [ticket/12269] Delete folder mods in language
[ticket/9040] Count HTML entities as single in custom profile fields

Currently when an user adds a HTML entity to a custom profile field, the length
gets incremented by 4 since the code reads &gt; instead of <. However, the
length is presentational and not DB storage so it should be treated as a
single character even if it takes four lengths in the DB by being stored as
a HTML entity.

Work around this by decoding html entities before counting. Also, added unit
tests for string field type

PHPBB3-9040
[ticket/9040] Minor cleanup in the unit test file

PHPBB3-9040
Merge remote-tracking branch 'dragooon/ticket/9040' into develop

* dragooon/ticket/9040:
  [ticket/9040] Minor cleanup in the unit test file
  [ticket/9040] Count HTML entities as single in custom profile fields
[ticket/12279] Add memberlist_view.html template event to add custom info

Template event to ddd custom content
to the user profile view after the main content.

PHPBB3-12279
Merge remote-tracking branch 'vsephpbb/ticket/7580' into develop

* vsephpbb/ticket/7580:
  [ticket/7580] Add test for IF {VAR} is defined in templates
Merge remote-tracking branch 'rxu3/ticket/12279' into develop

* rxu3/ticket/12279:
  [ticket/12279] Add memberlist_view.html template event to add custom info