[ticket/11780] Remove unused images

PHPBB3-11780
[ticket/11780] Remove references to unused images

PHPBB3-11780
[ticket/11781] Include func update_post_information()

Include functions_posting before using functions defined in that file

PHPBB3-11781
[ticket/11777] Add subdirectory 'events/' to the template event search path

Makes the twig template engine look in the events/ subdirectory instead of the
main styles/[style]/template/ directory for extension template events. Note
that it does _not_ look recursively!

PHPBB3-11777
[ticket/11777] Move the testing template events to 'events/' subdirectories

The tests written for extension template events did not follow the convention
and documentation of placing template event files in the events/ subdirectory.
Moved the files to this subdirectory so the tests succeed again.

PHPBB3-11777
[ticket/11777] Rename the extension template listener subdirectory to 'event/'

Per suggestion of EXreaction and nickvergessen, do not look for extension
template event listeners in styles/[style]/template/events/ but in
styles/[style]/template/event/ (without the trailing 's') to match the way
phpBB looks for php template event listeners.

PHPBB3-11777
[ticket/11777] Require a suffix of '_listener' on extension template listeners

To further mirror the file name and location requirements for php template
event listeners, require extension template event listener files to follow the
'<event name>_listener.html' naming format.

PHPBB3-11777
[ticket/11777] Fix new test for loop variables in extension template listeners

With the merge of https://github.com/phpbb/phpbb3/pull/1564 a new test has
been added. Renamed and moved the template listener file of that test to
comply with the new requirements.

PHPBB3-11777
Merge remote-tracking branch 'cyberalien/ticket/11780' into develop

* cyberalien/ticket/11780:
  [ticket/11780] Remove references to unused images
  [ticket/11780] Remove unused images
Merge remote-tracking branch 'cyberalien/ticket/11781' into develop

* cyberalien/ticket/11781:
  [ticket/11781] Include func update_post_information()
Merge pull request #1643 from rechosen/ticket/11777

[ticket/11777] Search for template listeners in the php event listeners way
[feature/only-op-can-view] ACP language keys and SQL data

Include the f_read_other permission in the DB. Defaults to true
Two new roles:
- ROLE_DESCRIPTION_FORUM_STANDARD_NO_OTHER <-like standard without f_read_other
- ROLE_DESCRIPTION_FORUM_LIMITED_NO_OTHER <-like limited without f_read_other

Altering other "f_" ROLES so that they include the f_read_other as true (1)

Added the language keys for f_read_other (requires adding a tab before all "=>"

PHPBB3-10624
[feature/only-op-can-view] Adding ACP language keys

Adding the language keys  for the ACP roles systema and explanation about each
role.
The big amount of lines changed is caused by a need to add a tab before "=>" in
all lines so that all the "=>" may match from line to line

PHPBB3-10624
[feature/only-op-can-view] Bug fix: git destroyed permissions.php

This is the fix to remove the file git destroyed caused by a misplaced head.
This removes the git marks and the previous version form the file.

PHPBB3-10624
[feature/only-op-can-view] Apply to feeds.php

After applying this feature to the ACP, now the feature is also applied to
the feeds.php.
Many tests were made to make sure that it is working as it should. Please
test and confirm that all is working properly.

PHPBB3-10624
[feature/only-op-can-view] Follow code guidelines in feeds.php

There was a mistake in feeds.php where it wasn0t following the coding
guidelines.

PHPBB3-10624
[feature/only-op-can-view] Viewforum Edit. Apply this to viewforum

- New template variable to forumlist_body.html -> FORUM_PRIVATE
- forumlist_body.html tweaked:
 - If the user can only see his posts then:
  - He cannot see the number of posts. -> "?" appears
  - He cannot see the number of topics. -> "?" appears
  - He cannot see the last post. Finding it would create a significant overhead
    caused by both PHP and DBMS processing. May be added in the future as an
    option. Anyway, this is the way most other forums act.
- viewforum.php:
 - If the user has limited access, the topic recount is used.
 - To prevent too much overhead by many if's, if sort_days exist, then solve
   everything in 1 if. Probably the code can be considered cleaner this way.

- New language key "PRIVATE_FORUM_FORUM".
 - Used to replace the last post date, image link and author in
   forumlist_body.html

Notes:
 Announcements and global announcements are not filtered. This is no bug, this
 is made like that by design. It's useful for the forum admins/mods to be able
 to post topics in a way everyone can see.

 Unless there's a bug, it's now officialy impossible to get to every single post
 that can exist in a forum though viewforum (not search.php)
 if you don't have the right to see other's posts.
 Same happens for the real number of posts, the last poster of the forum,
 the number of topics and any other information that can lead to people
 thinking or finding out that there are more posts inside that forum than
 announcements, global announcements and topics they started by (him/her)self.

PHPBB3-10625
[feature/only-op-can-view] Feeds changes

Improved a comment to be more expressive.
After some discussion, it was decided that news should also be filtered.

PHPBB3-10625
[feature/only-op-can-view] The search.php edits

search.php seems to be completly "sealed"
My search shows that all that only-op-can-view is now completly applied to
search.php now.

PHPBB3-10625
[feature/only-op-can-view] Altering forum listing

I was suggested a while ago to do this but I had forgotten. Now I have applied
the suggested changes. Make it show just like it shows with links
replacing forums (a forum of type link). This also allows not to use the '?'.
Is this way ok?

PHPBB3-10625