Update template, add info on features and image metadata (#51)

* Update template, add info on features and image metadata

* Typo

* Remove redundant README note

* Language correction

.devcontainer/devcontainer.json

@@ -1,37 +1,29 @@
-// For format details, see https://aka.ms/vscode-remote/devcontainer.json or this file's README at:
-// https://github.com/microsoft/vscode-dev-containers/tree/v0.195.0/containers/java
+// For format details, see https://aka.ms/devcontainer.json. For config options, see the
+// README at: https://github.com/devcontainers/templates/tree/main/src/java
 {
 	"name": "Java",
-	"build": {
-		"dockerfile": "Dockerfile",
-		"args": {
-			// Update the VARIANT arg to pick a Java version: 8, 11, 17
-			// Append -bullseye or -buster to pin to an OS version.
-			// Use the -bullseye variants on local arm64/Apple Silicon.
-			"VARIANT": "17-bullseye",
-			// Options
-			"INSTALL_MAVEN": "true",
-			"MAVEN_VERSION": "3.8.5",
-			"INSTALL_GRADLE": "false",
-			"NODE_VERSION": "lts/*"
+	// Or use a Dockerfile or Docker Compose file. More info: https://containers.dev/guide/dockerfile
+	"image": "mcr.microsoft.com/devcontainers/java:0-17",
+
+	"features": {
+		"ghcr.io/devcontainers/features/java:1": {
+			"version": "none",
+			"installMaven": "true",
+			"mavenVersion": "3.8.6",
+			"installGradle": "false"
 		}
 	},
-		
+
 	// Configure tool-specific properties.
 	"customizations": {
 		// Configure properties specific to VS Code.
 		"vscode": {
-			// Set *default* container specific settings.json values on container create.
-			"settings": { 
-				"maven.executable.path": "/usr/local/sdkman/candidates/maven/current/bin/mvn"
-			},
-			
-			// Add the IDs of extensions you want installed when the container is created.
+			"settings": {},
 			"extensions": [
-				"vscjava.vscode-java-pack"
+				"streetsidesoftware.code-spell-checker"
 			]
 		}
-	},
+	}
 
 	// Use 'forwardPorts' to make a list of ports inside the container available locally.
 	// "forwardPorts": [],
@@ -39,6 +31,6 @@
 	// Use 'postCreateCommand' to run commands after the container is created.
 	// "postCreateCommand": "java -version",
 
-	// Uncomment to connect as a non-root user. See https://aka.ms/vscode-remote/containers/non-root.
-	"remoteUser": "vscode"
+	// Uncomment to connect as root instead. More info: https://aka.ms/dev-containers-non-root.
+	// "remoteUser": "root"
 }