Unicorn 0.8.1

Unicorn has been updated to 0.8.1
Unicorn is a Rack HTTP server for Unix, fast clients and nothing else

This release features safer, more descriptive timeout handling, more
consistent reload behavior, and is a miniscule amount faster on
“Hello World” benchmarks.

Eric W. (7):
doc: cleanup summary/description
Fix potential race condition in timeout handling
SIGHUP reloads app even if preload_app is true
Make our HttpRequest object a global constant
Avoid instance variables lookups in a critical path
Consistent logger assignment for multiple objects
unicorn 0.8.1