Hi thanks for providing this gem. very helpful! I was wondering if there were specific reasons the `json` dependency is set at [`~> 2.1`](https://github.com/intuit/oauth-rubyclient/blob/14aeaeb5e63b8c16cb5c9886da43c96526eb9ad8/intuit-oauth.gemspec#L8)? Would there be any adverse effect if the dependency is relaxed to also allow `1.8.x`? Thanks!