JDF-694 Fixed the parsing of invalid Dates at client-side.

Invalid dates input by a user, but having a valid date format are
validated using this fix. A temporary Date instance is created and
it's components verified against the user input.

This fix does not correct the behavior of the server to convert
the provided Date into a valid one.
JDF-703 Improved the REST semantics for the backend.

Contacts are now updates via PUT /contacts/{id}.
They're deleted via a DELETE /contacts/{id}.

HTTP 404 responses are sent when {id} does not correspond to an
existing one.

HTTP 409 is sent if the contact's Id is updated in a PUT.
Update the name of the JavaScript module from APPMODULE to CONTACTS.