v1.1: Replace DB statements

[webbird]

This issue collects commits concerning the switch to the Doctrine DBAL. We should prefer to use prepared statements whenever possible.

[webbird]

Simple way to use prepared statement with little effort (example taken from CAT_Helper_Addons):

$addon = $self->db()->query(
            'SELECT * FROM `:prefix:addons` WHERE addon_id=:id',
            array('id'=>$id)
        );

Please note that there is no need to use something like 'SELECT * FROM '.CAT_TABLE_PREFIX.'tablename ...' or sprintf( 'SELECT * FROM %stablename ...',CAT_TABLE_PREFIX) anymore. The :prefix: placeholder will be replaced by the class.database.php.

[webbird]

I've renamed some methods. Old methods are still available with $database global.

is_error -> isError get_error -> getError set_error -> setError (private)

New:

qb() -> returns Query Builder object conn() -> returns connection object resetError() -> cleans up error stack prefix() -> returns CAT_TABLE_PREFIX prepare() -> wrapper for PDO prepare(), replaces :prefix: in query string