Update vscode config (#2105)

* Add null analysis, format on modification, prettier config and recommended extensions to vscode settings.

* Remove gradle extension from recommended

.gitignore

@@ -48,4 +48,5 @@ appveyor.yml
 javadoc_deploy
 javadoc_deploy.pub
 !.vscode/settings.json
-!.vscode/JME_style.xml
+!.vscode/JME_style.xml
+!.vscode/extensions.json

.vscode/extensions.json

@@ -0,0 +1,6 @@
+{
+	"recommendations": [
+                "vscjava.vscode-java-pack",
+                "slevesque.shader"
+	]
+}

.vscode/settings.json

@@ -1,7 +1,15 @@
 {
     "java.configuration.updateBuildConfiguration": "automatic",
+    "java.compile.nullAnalysis.mode": "automatic",
     "java.refactor.renameFromFileExplorer": "prompt",
     "java.format.settings.url": "./.vscode/JME_style.xml",
     "editor.formatOnPaste": true,
-    "editor.formatOnType": true
+    "editor.formatOnType": false,
+    "editor.formatOnSave": true,
+    "editor.formatOnSaveMode": "modifications" ,
+
+    "prettier.tabWidth": 4,
+    "prettier.printWidth": 110,
+    "prettier.enable": true,
+    "prettier.resolveGlobalModules": true
 }