These changes should solve the strict standards error about accessing
the non-static get_instance() in a non-static way.
For that, I changed the get_instance methods to static methods.
PHPBB3-10575
The base class for captcha plugins has been renamed, but the old name continues
to exist as an empty subclass of it for backwards compatability.
PHPBB3-10323
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
Closing tags converted using Oleg's script.
remove-php-end-tags.py -a .
Trailing newlines added using the following where $ext is file extension.
find . -type f -name "*.$ext" -print | xargs printf "e %s\nw\n" | ed -s;
Extensions: php, css, html, js, xml.
PHPBB3-9556
