Fixed returned number of processors on Mac OSX.

[bamse16]

Fixed returned number of processors on Mac OSX. Tested on Mac OSX (and Ubuntu). Source: http://stackoverflow.com/questions/150355/programmatically-find-the-number-of-cores-on-a-machine

[BlinkyStitt]

Samr7 hasn't been active with this repo so I merged this into my fork at https://github.com/WyseNynja/vanitygen. It's easy to install with my brew tap at https://github.com/WyseNynja/homebrew-bitcoin and has various other fixes.

[kenorb]

Follow-up: https://github.com/exploitagency/vanitygen-plus