Fixed uninstall script

Fixed SQL query referencing Joomla 1.5 schema preventing clean uninstall
Strict standards compliance
Fixed category generation

Categories will now be inserted into the tree correctly.
Created advanced options for component backend

Sets lesser-used options to be hidden by default; power users can modify
them if they like but most users will not need to
v0.4.1

PHP 5.3+ fixes & backend changes