Add Felix Geisendörfer's HTTP stress test.
Add Felix Geisendörfer's HTTP stress test.

Does not pass on Macintosh and FreeBSD.

dreamllq/node,dreamllq/node,isaacs/nshtools,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node,dreamllq/node