Updated AuthToken to help marshalling/unmarshalling TimeStamp by JAXB. 

Moved AuthToken test into this module from another. 

Updated GSON to read/write in Timestamp compatible format
Updated auth client test to check for timestamp fields. 

Updated sample JSON to jive with new timestamp format going into/out of JSON
Moved commons-io versioning to dependencymanagement section in parent
Fixed parameter naming, set javaType argument to AuthToken result mapper
Updated getTokenById function name
Merge pull request #16 from isuftin/master

The main fix here is for AuthToken marshalling