Docblock updates and changes in code style for references to match merlin's ($a = &$b instead of $a =& $b)

Considerable refactoring. The separation between logic/loading functions and rendering functions is almost complete, now.

Shifted all possible render preparation functions into panels_page.render.inc; also added an @file description to it.

Panels Page now installs successfully, although the schema is likely going to change. The essential infrastructure for the menu system is functioning correctly. The secondary router storage mechanism, page callbacks, temporary panel data storage mechanism (for render callbacks) and a few other things need to be designed - but we're on the home stretch.