Limit class exposure to end users

[jzheng2017]

Currently the library exposes a lot of internal details, a lot of classes are public. This may not be desirable as end users of the library shouldn't know of the implementation details.

A great enhancement would be to limit the exposure of implementation classes.

Only the following classes should be exposed:

• SpotifyApi
• AuthorizationCodeFlow
• AuthorizationCodeFlowPKCE
• AuthorizationPKCERequestToken
• AuthorizationRefreshToken
• AuthorizationRequestToken
• ClientCredentialsFlow
• All of the domain model objects

[Whxismou1]

Hi, it´s this issue still open?

[jzheng2017]

Yes, it is. When working on this please branch off the 2.0.0 branch since you will be making breaking changes.

[Whxismou1]

Okay, I'll get to work on it. Any additional observations I should take into account?