Removed joda time dependency and will use standard java date time instead.  While joda time is nice, there is a lot of config for it in order to serialize/deserialize and in order to map within jpa.  Was alot of work for little gain since the date times in this context are really just being passed back and forth and not having any logic performed on them.
Fixed issue with auto generated id values not working for postgresql database.
Added support for creating todo objects.  Updated todo dao to return id of newly created todo object so that a created header can be returned upon successful creation
Enclosed readById in try/catch block in order to catch NoResultsException and throw null so the service can return a 404.  Added new method for delete that takes a id.
Updated Cors filter with new headers to allow POST to work correctly.
Added restful methods for read all todos, modify todo and delete todo.  Added support function in dao to check if an entity already exists or not.