Bugfixings in Config

- replaced usage of "!<unset>!" with null-returns
- fixed bool settings (0/1)
- fixed overriding config-values
- fixed basepath problems

src/Core/PConfig.php

@@ -65,8 +65,6 @@ class PConfig
 	/**
 	 * @brief Sets a configuration value for a user
 	 *
-	 * @note  Please do not store booleans - convert to 0/1 integer values!
-	 *
 	 * @param string $uid    The user_id
 	 * @param string $cat    The category of the configuration value
 	 * @param string $key    The configuration key to set