Crash using over 2000 fibers

[alexjc]

Nice project! Love the idea.

I found out about this via Javier's blog, and ran the code from this tutorial:
http://javier.gr/blog/2014/02/python-green-threads-fibers-golang/

... and indeed it crashes somewhere over 2000 fibers.

[saghul]

I'll look into the python-fibers crash. A fibers-only test case would help though :-)