src/utils/unique.js
function unique( target, arrays )
{
	target = target || [];
	var combined = target.concat( arrays );
		target 	 = [];

	var len = combined.length,
		i = -1,
		ObjRef;

		while(++i < len) {
			ObjRef = combined[ i ];
			if( target.indexOf( ObjRef ) === -1 && ObjRef !== '' & ObjRef !==  (null || undefined) ) {
				target[ target.length ] = ObjRef;
			}
		}
		return target;
}
function unique( target, arrays )
{
	target = target || [];
	var combined = target.concat( arrays );
		target 	 = [];

	var len = combined.length,
		i = -1,
		ObjRef;

		while(++i < len) {
			ObjRef = combined[ i ];
			if( target.indexOf( ObjRef ) === -1 && ObjRef !== '' & ObjRef !==  (null || undefined) ) {
				target[ target.length ] = ObjRef;
			}
		}
		return target;
}
function unique ( target , arrays ) { target = target || [ ] ; var combined = target . concat ( arrays ) ; target = [ ] ; var len = combined . length , i = - 1 , ObjRef ; while ( ++ i < len ) { ObjRef = combined [ i ] ; if ( target . indexOf ( ObjRef ) === - 1 && ObjRef !== '' & ObjRef !== ( null || undefined ) ) { target [ target . length ] = ObjRef ; } } return target ; }
join two arrays and prevent duplication
@param  {array} target
@param  {array} arrays
@return {array}
join two arrays and prevent duplication