Features

#234 Use FLAGR_WEB_PREFIX for both main api and flagr UI
#243 Add notes support. Thanks to @crberube
#247 Add EvalOnlyMode and extend DBDriver with json_file and json_http. People can decouple DB from eval cache if people want to opt-in these options.

Bug Fixes

#242 Remove entity_type statsd tag due to its possible high cardinality