Created by: sdwilsh
Test Plan: Ensured that following pages were properly selected when viewed:
- http://localhost:9811/concept/build_rule.html
- http://localhost:9811/concept/build_target.html
- http://localhost:9811/concept/build_file.html
- http://localhost:9811/concept/buckversion.html
- http://localhost:9811/concept/nobuckcheck.html
- http://localhost:9811/concept/buckjavaargs.html
- http://localhost:9811/concept/buckconfig.html
- http://localhost:9811/concept/build_target_pattern.html
- http://localhost:9811/concept/visibility.html
- http://localhost:9811/concept/http_cache_api.html
- http://localhost:9811/concept/rule_keys.html