Tests for out of range integers

This patch adds tests for,
1. out of range integers in the JSON request
body. Refer https://trello.com/c/0anf1cMf/331-json-integer-overflowerror.
2. negative integers in grace & TTL for claims.

Tests: bug #1202846

Change-Id: I100911edf20701b16bee31949fde65148e8e4e01
Merge "Tests for out of range integers"