Add PAWN language

PAWN is a simple, typeless, 32-bit extension language with a C-like syntax. A pawn "source" program is compiled to a binary file for optimal execution speed. The pawn compiler outputs P-code (or bytecode) that subsequently runs on an abstract machine. Execution speed, stability, simplicity and a small footprint were essential design criteria for both the language and the abstract machine. 

[Official Website](http://www.compuphase.com/pawn/pawn.htm)
[Where is PAWN used?](http://www.compuphase.com/pawn/pawnprojects.htm)

You can see [here](https://github.com/search?q=%23include+%3Ca_samp%3E&type=Code&ref=searchresults) PAWN is used for SA-MP and also [here](https://github.com/search?q=if+extension%3Apwn&type=Code&ref=searchresults) all the .pwn extensions in GitHub.