     Sends the a block to be run asynchronously on the main thread, in the current group.
 
     - parameters:
-    - block: The block that is to be passed to be run on the main queue
+        - block: The block that is to be passed to be run on the main queue
     */
     public func main(block: dispatch_block_t) {
         async(block: block, queue: GCD.mainQueue())

        QOS_CLASS_UTILITY, in the current block.

     - parameters:
     - block: The block that is to be passed to be run on the queue
     */
    public func utility(block: dispatch_block_t) {
        async(block: block, queue: GCD.utilityQueue())

     Block is run any given amount of times on a queue with a quality of service of QOS_CLASS_USER_INTERACTIVE. The block is being passed an index parameter.

     - parameters:
         - iterations: How many times the block should be run. Index provided to block goes from `0..<iterations`
         - block: The block that is to be passed to be run on a .
     */
    public static func userInteractive(iterations: Int, block: Int -> ()) {
        dispatch_apply(iterations, GCD.userInteractiveQueue(), block)
