Update to use rollup.js

Thanks @ljmerza!

.nvmrc

@@ -1 +0,0 @@
-v8.12.0

package.json

@@ -1,7 +1,7 @@
 {
     "name": "boilerplate-card",
     "version": "1.0.0",
-    "description": "A templatable config pass-through",
+    "description": "Lovelace boilerplate-card",
     "keywords": [
         "home-assistant",
         "homeassistant",
@@ -10,26 +10,28 @@
         "lovelace",
         "custom-cards"
     ],
-    "umd:main": "boilerplate-card.js",
+    "module": "boilerplate-card.js",
     "repository": "git@github.com:custom_cards/boilerplate-card.git",
-    "author": "Ian Richardson <iantrich@gmail.com>",
+    "author": "BoilerPlate <boilerplate@email.com>",
     "license": "MIT",
     "dependencies": {
         "lit-element": "^2.0.1"
     },
     "devDependencies": {
+        "@typescript-eslint/parser": "^1.4.1",
+        "eslint": "^5.14.1",
+        "eslint-plugin-typescript": "^0.14.0",
         "microbundle": "^0.10.1",
         "prettier": "^1.16.4",
-        "tslib": "^1.9.3",
+        "rollup": "^1.2.3",
-        "tslint": "^5.12.1",
+        "rollup-plugin-node-resolve": "^4.0.1",
-        "tslint-config-prettier": "^1.18.0",
+        "rollup-plugin-typescript2": "^0.19.2",
-        "tslint-eslint-rules": "^5.4.0",
-        "tslint-plugin-prettier": "^2.0.1",
         "typescript": "^3.3.3333"
     },
     "scripts": {
-        "start": "microbundle watch",
+        "start": "rollup -c --watch",
-        "build": "npm run lint && microbundle --external litElement --target browser --format umd",
+        "build": "npm run lint && npm run rollup",
-        "lint": "tslint index.ts"
+        "lint": "eslint src/index.ts",
+        "rollup": "rollup -c"
     }
 }

rollup.config.js

@@ -0,0 +1,14 @@
+import resolve from 'rollup-plugin-node-resolve';
+import typescript  from 'rollup-plugin-typescript2';
+
+export default {
+    input: 'src/index.ts',
+    output: {
+        file: 'boilerplate-card.js',
+        format: 'es'
+    },
+    plugins: [
+        resolve(),
+        typescript ()
+    ]
+};

src/index.ts

@@ -39,9 +39,3 @@ class BoilerplateCard extends LitElement {
     return css``;
   }
 }
-
-declare global {
-  interface HTMLElementTagNameMap {
-    "boilerplate-card": BoilerplateCard;
-  }
-}

tsconfig.json

@@ -1,13 +1,10 @@
 {
   "compilerOptions": {
-    "jsx": "react",
-    "jsxFactory": "h",
     "target": "es2017",
     "module": "esnext",
     "moduleResolution": "node",
     "lib": ["es2017", "dom", "dom.iterable"],
     "noEmit": true,
-    "noUnusedLocals": true,
     "noUnusedParameters": true,
     "noImplicitReturns": true,
     "noFallthroughCasesInSwitch": true,
@@ -17,4 +14,4 @@
     "resolveJsonModule": true,
     "experimentalDecorators": true
   }
-}
+}