Changes for Crypt-JWT distribution

0.008   2015/07/04
        - decode_jwt: new parameter - ignore_claims
        - fix related to nbf, iat, exp checks

0.007   2015/07/04
        - decode_jwt: new parameter - kid_keys

0.006   2015/07/03
        - after many changes first candidate for stable API
        - incomplete tests

0.001   2015/06/30
        - initial version