fixed distance measure unit display bug
consider 201/Created to be a successfull call

was failing on first call to adding an apiSubscription
added an afterHistoryUpdate callback

mainly for fetching a backlog of manual entries for fitbit
fixed error code for conflicting api subscription
added utility endpoint to manage fitbit apiSubscriptions

only 1 apiSubscription/user/key :-(
backsync has to happen right after history update
Merge branch 'release/1.1.2' into development
reset time series fetching to the max

added more default channels
CORS allowed origins: allow PUT too
only send positive values to the datastore
leverage start- and end- timeStorage to compute local time
Merge branch 'development' into release/1.1.2