Fixed a bug when reading from the database.

The MongoDB bin for ExternalAuthorizationInformation objects was incorrectly deserializing the objects. This has been fixed.

Closes #9
Add the fitbit api jar.
Add the beginnings of a Fitbit shim.
Hardcode some data to be returned from the shim.
Add in the Fitbit API and enough shim code to fetch a single steps
datapoint.
Add in a missing dep for fitbit4j.
Fix up the access token secret stuff.
Clean up the steps fetching code and get ready for adding more data
types.
Expose some more data fields for activity.
Add some sleep data.
Fix up everything for the latest upstream changes.
Fix the returned schema IDs to have the prefix attached.
Add the most of a withings shim that can fetch 4 different data types.
Add rest of withings measure types and schemas.
Refactored schema fetching.
Don't need that empty constructor...
Add a doc comment for getSchema.
Add start date, end date, num to skip, and num to return support to the
withings shim.
Move withings client id and secret to a properties file.
Add some excpetions on missing shim properties.