feat(transport): define acceptable integer range

The JSON parser in use (simplejson) supports Python big integers,
while none of the storage drivers can serialize them.  The acceptable
range to both bson and msgpack is -2^63 ~ 2^63-1.

Change-Id: I861201ea5493bbe4e1c0197000edbd8594162047
Fixes: bug #1202846
Merge "feat(transport): define acceptable integer range"