Add a file storage to plugin registry

This MR adds a simple file store to the plugin registry.

Description

The file store allows a very basic and simple persistence of plugins. The aim is to provide a simple implementation that allows plugin information to be available even after a restart of the registry.

Related Issue

Motivation and Context

Currently UUIDs for plugins within the registry have been hard-coded.

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.

plugin-registry/main.go

@@ -66,14 +66,15 @@ func registerPlugins() *PluginRegistry {
 				panic(err)
 			}
 
-			dirHashed, err := dirhash.HashDir(dirPath, dir.Name()+manifest.Firmware, dirhash.DefaultHash)
+			zipPath := filepath.Join(dirPath, util.BundledPluginName)
+			zipHashed, err := dirhash.HashZip(zipPath, dirhash.DefaultHash)
 			if err != nil {
 				panic(err)
 			}
 
 			var plugin *Plugin
 			for i, p := range plugins {
-				if p.Hash == dirHashed {
+				if p.Hash == zipHashed {
 					plugin = p
 					plugins[i] = plugins[len(plugins)-1]
 					plugins = plugins[:len(plugins)-1]
@@ -85,7 +86,7 @@ func registerPlugins() *PluginRegistry {
 				plugin = &Plugin{
 					ID:       uuid.New(),
 					Path:     filepath.Join(dirPath, util.BundledPluginName),
-					Hash:     dirHashed,
+					Hash:     zipHashed,
 					Manifest: manifest,
 				}
 			}