Use rsa pub and private keys for jwt

[adred]

I don't entirely understand how JWT works yet but I noticed that Echo middleware for JWT only uses one key(I assume for both generation and validation). However, github.com/SermoDigital/jose encourages us to use rsa private key for generating token and rsa pub key for validating token. Should I be concerned that Echo's implementation is different? I have Echo jwt integrated and working in my app but I kinda feel it should follow jose specifications. Someone created examples here: https://gist.github.com/nanoninja/50e56791d13d340068ccf4f6c810dbf7

Thoughts?

[benbjurstrom]

See #633 for a JWT middleware example using the RS256 algorithm.