* added comments for the angular loader.

* added code documentation for backendSrv.

* docs for datasource_srv.

* added some more docs.

* added documentation for the locationsrv.

* started to add docs for echo srv.

* added docs for meta srv.2

* added docs for analytics.

* draft documentation of the DataSourceWithBackend.

* added docs for last files.

* fixed all warnigns in api-extractor.

* fixed some typos and captializations.