Support ethr did in the JS IDM Client

[satazor]

Description

Support ethr did in the JS IDM Client. This task is easy because we are using https://github.com/uport-project/did-resolver and there's already https://github.com/uport-project/ethr-did-resolver!

Acceptance Criteria

• Integrate https://github.com/uport-project/ethr-did-resolver into the IDM Client into did-resolver, the file that configures did-resolver: https://github.com/ipfs-shipyard/js-idm-client/blob/master/src/did-resolver.js

[vasa-develop]

@satazor
I think this is done in this PR.