[ticket/10258] Remove copyright meta tag from docs

It fails HTML5 validation and we already have a 'copyright and
disclaimer' section in all of those documents. We can always represent
the copyright more semantically later (such as the HTML5 <copyright>
tag).

PHPBB3-10258
Merge branch 'prep-release-3.0.9'

* prep-release-3.0.9: (359 commits)
  [prep-release-3.0.9] Bumping version number for 3.0.9 final.
  [prep-release-3.0.9] Update Changelog for 3.0.9-RC4 release.
  [prep-release-3.0.9] Decreasing version for an RC4 release.
  [ticket/9859] Changing all phpBB footers to match the new credit line
  [ticket/9859] New footer copyright line with registered symbol
  [ticket/10250] The site_logo hash is different depending on imageset & language
  [ticket/10250] Destroy cached md5 hash of site_logo on refreshing an imageset
  [ticket/10250] Overwrite the site_logo width&height when the phpbb logo is used
  [ticket/10247] Remove attempt_id as primary key from database_update.php
  [ticket/10250] Added the new phpBB Logo with the Registered Trademark Symbol
  [ticket/10247] Use COUNT(*) instead of COUNT(attempt_id)
  [prep-release-3.0.9] Update Changelog for 3.0.9 release.
  [prep-release-3.0.9] Bumping version number for the final 3.0.9 release.
  [ticket/10247] Removing attempt_id column from the 3.0.8 to 3.0.9-RC1 updater.
  [ticket/10247] Add a db_tools test for the removal of a primary key column.
  [ticket/10247] Add empty data section to database update for RC4
  [ticket/10247] Remove unecessary attempt_id primary key column
  [prep-release-3.0.9] Bump database version to RC3 too.
  [prep-release-3.0.9] Update Changelog for 3.0.9-RC3 release.
  [prep-release-3.0.9] Bumping version number for 3.0.9-RC3.
  ...
[ticket/10258] Adjust some deprecated tags for HTML5 in coding-guidelines

PHPBB3-10258
[ticket/10155] Add jQuery, introduce global assets path

Add the jQuery JavaScript library to all pages, giving modifications
instant access and allowing for any future core JavaScript to take
advantage of it.

Also introduce a global /assets directory for assets that are shared
between styles.

PHPBB3-10155
[ticket/10258] Remove the meta charset tag

The charset tag is useless, because if a charset content-type header is
present it takes precedence. And phpBB always sends such a header.

PHPBB3-10258
[ticket/10260] Remove prosilver styleswitcher

The styleswitcher is an odd invention that allows setting the font size
of the page dynamically via JavaScript (and CSS). This should be done by
browser settings instead.

PHPBB3-10260
[ticket/10155] Add jQuery to AUTHORS

PHPBB3-10155
[ticket/10155] Update to jQuery 1.6.2

PHPBB3-10155
[ticket/9608] Remove use of references in captcha and other places

References are not really needed in PHP due to copy-on-write. Since
PHP5, objects are always passed around as identifiers, which means they
are mutable. So it is no longer required to pass these by reference
either.

PHPBB3-9608
[ticket/7090] Update documented minimum PHP version to  5.2.0

PHPBB3-7090
Merge remote-tracking branch 'igorw/ticket/7090' into develop

* igorw/ticket/7090:
  [ticket/7090] Update documented minimum PHP version to  5.2.0
Merge branch 'develop-olympus' into develop

* develop-olympus:
  [ticket/10255] Add leading slash in gitignore to only ignore specified files

Conflicts:
	.gitignore
Merge branch 'develop-olympus' into develop

* develop-olympus:
  [ticket/10267] Call strlen() on $table_prefix for $max_length calculation.
Merge branch 'develop-olympus' into develop

* develop-olympus:
  [ticket/10216] Fixed a grammar error in SOME_QUERIES_FAILED.
Merge branch 'ticket/igorw/10260' into develop

* ticket/igorw/10260:
  [ticket/10260] Remove prosilver styleswitcher
[feature/request-class] Add server(), header() and is_ajax() to request

Extend the request class with helpers for reading server vars (server())
and HTTP request headers (header()). Refactor the existing code base
to make use of these helpers, make $_SERVER a deactivated super global.

Also introduce an is_ajax() method, which checks the X-Requested-With
header for the value 'XMLHttpRequest', which is sent by JavaScript
libraries, such as jQuery.

PHPBB3-9716
[ticket/10260] Remove the icon_fontsize.gif image (thanks Vinny)

PHPBB3-10260
Merge remote-tracking branch 'igorw/ticket/10260' into develop

* igorw/ticket/10260:
  [ticket/10260] Remove the icon_fontsize.gif image (thanks Vinny)
Merge branch 'develop-olympus' into develop

* develop-olympus:
  [ticket/10208] Explain what happens when 'Warning duration' is set to 0.
[feature/request-class] Minor spacing CS adjustments

PHPBB3-9716