typo in tutorial #20

From old Google Code repo:

Reported by mjanos5, Jan 15, 2012

http://code.google.com/p/python-csp/wiki/Tutorial

problem:

typo in:

CSP stands for Communicating Sequential Processes, which is a framework for writing concurrent or program via message passinge.

solution:

Change it to:

CSP stands for Communicating Sequential Processes, which is a framework for writing concurrent or program via message passing.