Completely removes specified preference(s)
@param {String} name Preference name (or array of names)
function(name) {
			if (!_.isArray(name))
				name = [name];
			
			_.each(name, function(key) {
				if (key in preferences)
					delete preferences[key];
				
				if (key in defaults)
					delete defaults[key];
			});
		}