feat: use grafana-toolkit to build a plugin

- fix linter warnings
- use yarn: remove Gruntfile.js and package-lock.json

++

tsconfig.json

@@ -1,55 +1,35 @@
 {
+  "extends": "./node_modules/@grafana/toolkit/src/config/tsconfig.plugin.json",
   "compileOnSave": false,
   "compilerOptions": {
-    "moduleResolution": "node",
-    "outDir": "dist",
-    "target": "es5",
-    "lib": ["es6", "dom"],
-    "rootDir": ".",
-    "module": "esnext",
     "allowJs": true,
     // Don't emit; allow Babel to transform files.
-    "noEmit": true,
-    // Enable strictest settings like strictNullChecks & noImplicitAny.
-    "strict": true,
+    //"noEmit": true,
     // Disallow features that require cross-file information for emit.
-    "isolatedModules": true,
-    "declaration": false,
-    "allowSyntheticDefaultImports": true,
-    // Import non-ES modules as default imports.
-    "esModuleInterop": true,
-    "forceConsistentCasingInFileNames": true,
-    "importHelpers": true,
-    "noEmitHelpers": true,
+    //"isolatedModules": true,
+
     "removeComments": false,
     "inlineSourceMap": false,
-    "sourceMap": true,
     "emitDecoratorMetadata": false,
-    "experimentalDecorators": true,
     "strictNullChecks": false,
-    "noImplicitReturns": true,
-    "noImplicitThis": true,
-    "noImplicitUseStrict": false,
     "noImplicitAny": false,
+    "noImplicitUseStrict": false,
     "noEmitOnError": false,
-    "downlevelIteration": true,
-    "noUnusedLocals": true,
-    "pretty": true,
-    "typeRoots": ["./node_modules/@types" ] // , "./src/types" ]
-    //"types": [
-    //  "lodash"
-    //]
-    ,
-    "baseUrl": ".",
-    "paths": {
-      "app/*": ["./node_modules/@types/grafana/app/*"]
-    }
+
+    "rootDir": "./src",
+    "baseUrl": "./src",
+    "outDir": "dist",
+    "typeRoots": [
+      "./node_modules/@types",
+      "./src/types"
+    ]
   },
   "include": [
-    "src/**/*.ts"
+    "src",
+    "types"
   ],
   "exclude": [
-    "node_modules",
-    "**/*.spec.ts"
+    "dist",
+    "node_modules"
   ]
 }