Initial implementation of fluent-style API for gribigo.

[robshakir]

    Initial implementation of fluent-style API for gribigo.
    
      * (M) client/client.go
      * (M) client/client_test.go
        - Rename client.NewClient to simply client.New to remove
          stuttering in the API call.
      * (A) fluent/fluent.go
      * (A) fluent/fluent_test.go
        - Initial implementation of the fluent API that can be used
          by test authors to test gRIBI functions.
        - Tests in this package also serve as integration tests between
         the client and the server within the package.
      * (M) go.mod
      * (M) go.sum
        - Go module housekeeping.
      * (M) server/server.go
      * (M) server/server_test.go
        - Update server code to move to using New() vs. NewServer() to
          remove stuttering.

This PR fixes the erroneous merge to main directly. Added branch protection for this branch requiring PR reviews so this should not happen again.