CGI::QueryExtension

Mixin module. It provides the follow functionality groups:

1. Access to CGI environment variables as methods. See documentation to the CGI class for a list of these variables.
2. Access to cookies, including the cookies attribute.
3. Access to parameters, including the params attribute, and overloading

   to perform parameter value lookup by key.

4. The initialize_query method, for initialising the above mechanisms, handling multipart forms, and allowing the class to be used in "offline" mode.