Create authentication to Fitbit authentication service backend

[blootsvoets]

At least basic authentication should added to radar fitbit authorisers. https://github.com/RADAR-base/RADAR-Docker/blob/f33ce18d901e56f3c68864e3632a783d4f9efa13/dcompose-stack/radar-cp-hadoop-stack/etc/webserver/optional-services.conf.template#L8 https://github.com/RADAR-base/RADAR-Docker/blob/f33ce18d901e56f3c68864e3632a783d4f9efa13/dcompose-stack/radar-cp-hadoop-stack/etc/webserver/optional-services.conf.template#L13

[nivemaham]

I was under the impression that this was already there. Now I get it

[yatharthranjan]

The lates rest sources has auth from Management portal so just need to upgrade and migrate to latest version of rest-source-auth.