read BG thresholds and alarm types from ENV and make them available to the server and api
read BG thresholds from api; refactor init so that it happend after we get basic settings from api
emit alarms based on ENV ALARM_TYPES (simple and predict)
updated BG_HIGH default to 240
cleanup
preseve current behavior is new BG_* and ALARM_TYPES ENV isn't set

also some cleanup of the int ENV parsing
Merge pull request #21 from nightscout/wip/jingle-bells

Wip/jingle bells