Avoid string -> byte allocations. ``` BenchmarkParseJWTStandardClaims-32 3527152 343.2 ns/op 1489 B/op 21 allocs/op BenchmarkParseJWTStandardClaims-32 4713199 259.2 ns/op 706 B/op 16 allocs/op BenchmarkParseJWTMapClaims-32 2666668 448.7 ns/op 1883 B/op 32 allocs/op BenchmarkParseJWTMapClaims-32 3120709 377.1 ns/op 1227 B/op 28 allocs/op ```
jwt-go has been renamed to jwt and has a new home. See https://github.com/dgrijalva/jwt-go/issues/462
This is to ensure that there are no projects that try to import `minio/minio/pkg` into their own repo. Any such common packages should go to `https://github.com/minio/pkg`