Remove Mongrel adapter
Remove Hatetepe adapter
Remove signal handlers
Remove Adapter#shutdown
Merge pull request #187 from seancribbs/backspace

Remove Mongrel, Hatetepe adapters, Adapter#shutdown, SIGINT handlers
Run RSpec with -b in CI
Refactor adapter_lint setup
Sleep a little less during adapter_lint setup
Add test covering IPv6 requests
Centralize request URI handling