Added commented xcconfigs for App bundle vs. sub_umbrella Framework Target build

From the .xconfig's comments....

>  You have TWO options for linking / including BlocksKit/any Mac framework..
> Option A: 	Inside your YourApp.app. 	(A private framework) This is how the included "Mac Demo App" does it.
> Option B: 	Inside YourKit.framework. (Yours is the "umbrella" framework, Blockskit becomes the "sub_umbrella")


Also fixed method mismatch in updated NSTimer call in demo app. and
erroneous 10.9 deployment targets.


![130903-0003](https://f.cloud.github.com/assets/262517/1072078/06aa9cb4-1487-11e3-8a2a-b3ce4737f455.png)