add GenerateEdDSA helper and origin_jti on standard claims

minor: add optional MaxAge field to the multiple keys signer

add multiple key ids configuration and an example

fix #8

add key ids helper and replace travis with github actions

add key ids helper and replace travis with github actions

Add support for public key per-token and add an example

Relative to: #2

Export the CompareHeader as variable in order to be customized as req…

…uested at: #2 (comment)

update to v0.0.8

fix #3

add a new Decode which just decodes the token in compact form without verification and validation

fix #2