Don't map JSON values to Double

Don't map JSON values to Double

By default, gson treats all numbers as Double when placed into a
generic Map.  This is not backward compatible with existing policy
APIs.  Added a type adapter that walks Map objects and converts the
Double values to Integer or Long, where possible.
Made this the default behavior in the GsonMessageBodyHandler, the
JacksonHandler, and the StandardCoder.
Also fixed a couple of checkstyle errors in the gson project.

Change-Id: I9ac0c77e6592d1c039646f0662c077b77a1e9aaf
Issue-ID: POLICY-1542
Signed-off-by: Jim Hahn <jrh3@att.com>