Update the RADIUS function reference for 1.3.0.

This has also resulted in some previously undocumented functions being
documented: there's still more that could be done there, and some of the
examples are pretty minimal, but it's a start.


git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@330790 c90b9560-bf6c-de11-be94-00142212c4b1
Add reference documentation for the RADIUS option constants, and link to it.


git-svn-id: https://svn.php.net/repository/phpdoc/en/trunk@330791 c90b9560-bf6c-de11-be94-00142212c4b1