FR: MFA support

[jasperkuperus]

Describe your environment

• Operating System version: All
• Firebase SDK version: v4.2.0
• Firebase Product: auth

Describe the problem

It would be nice if this library had support for MFA. Specifically, I'd like to get the enrolled second factors for a given user. For Node.js this is available and documented, but I don't see such a feature in this Go library. Are there any plans to add this?

[hiranya911]

No specific plans yet. But we are accepting PRs if somebody wishes to help speed things along.

[jasperkuperus]

Unfortunately, I don't have time to fully implement MFA. But I did just open a PR to add the MFA info to the user record. This already adds great value in my situation.

[hiranya911]

PR has been merged and updated to meet our API design requirements. This will be included in the next release.