Adding POSIX Threads to Natalie, Part 1

Wrapping POSIX pthreads turned out to be easier than I thought!

About the Project: Natalie a programming language that resembles Ruby, compiled to C. Find out more at the GitHub project page: https://github.com/seven1m/natalie ... https://www.youtube.com/watch?v=3BQFQS_4a9E