[Refactor] Auth-Server

[stravid87]

Description
The Auth Server contains a lot of legacy code that needs to be refactored and pruned.

List

• [handlers/Service.go line 67] func (u *Service) LoginUser(username, password string) (map[string]interface{}, error)

[stravid87]

See issue #245 for a list of more ideas for refactoring clean up.

[stravid87]

@interestIngc :what were some of the issue that you felt we should refactor or hadn't addressed yet?

Never mind, see it: "

layer8/server/internals/service/service.go

Line 67 in 3e027a0

// TODO: use SCRAM authentication here

-- A bug on the Auth Server I mentioned"