Resolve "Containerised Southbound Interfaces and the corresponding device config representation within the controller"

Description

Related Issue

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Closes #159 (closed)

nucleus/principalNetworkDomain.go

@@ -464,6 +464,11 @@ func (pnd *pndImplementation) createCsbiDevice(ctx context.Context, name string,
 	return nil
 }
 
+// requestPlugin is a feature for cSBIs and sends a plugin request to the cSBI
+// orchestrator and processes the received ygot generated go code, builds the plugin
+// and integrates the Plugin within the goSDN as SouthboundInterface. The
+// generated code is passed into a gostruct.go file, which is the foundation
+// for the created plugin.
 func (pnd *pndImplementation) requestPlugin(name string, opt *tpb.TransportOption) (southbound.SouthboundInterface, error) {
 	ctx, cancel := context.WithTimeout(context.Background(), time.Minute*10)
 	defer cancel()
@@ -514,6 +519,8 @@ func (pnd *pndImplementation) requestPlugin(name string, opt *tpb.TransportOptio
 	return loadPlugin(id, folderName)
 }
 
+// createPlugin builds a go plugin from ygot generated go code provided within
+// a plugin folder.
 func createPlugin(id uuid.UUID, folderName string) error {
 	pPath := folderName + id.String() + "/plugin.so"
 	sPath := folderName + id.String() + "/gostructs.go"
@@ -538,6 +545,8 @@ func createPlugin(id uuid.UUID, folderName string) error {
 	return nil
 }
 
+// loadPlugin loads a go plugin as SouthboundInterface from within a plugin
+// folder.
 func loadPlugin(id uuid.UUID, folderName string) (southbound.SouthboundInterface, error) {
 	p, err := plugin.Open(folderName + id.String() + "/plugin.so")
 	if err != nil {