Latest MaxOS API campatibility

[mmilen]

It appears the latest MacOS API requires MacOS 10.9 or newer. Is this correct.

When I try to run my Application on Mac OS 10.8.5 it fails with error NSURLSession not found.

[Lapo]

Yes, I think it is since release 1.6.0.

And yes, NSURLSession is only available in OS X 10.9 and higher.

[mmilen]

Add it to description, it is not clear. That you.