Implement our local package mymain

With `Main` component that render "Hello, world"

.gitignore

@@ -1 +1,2 @@
 node_modules
+build

packages/mymain/index.ts

@@ -0,0 +1 @@
+export * from './src';

packages/mymain/package.json

@@ -0,0 +1,9 @@
+{
+  "name": "mymain",
+  "version": "0.1.0",
+  "license": "UNLICENSED",
+
+  "main": "build/index.js",
+  "types": "build/index.d.ts",
+  "private": true
+}

packages/mymain/src/Main.tsx

@@ -0,0 +1,5 @@
+import * as React from 'react';
+
+export function Main() {
+  return <main>Hello, world</main>;
+}

packages/mymain/src/index.ts

@@ -0,0 +1 @@
+export * from './Main';

packages/mymain/tsconfig.json

@@ -0,0 +1,11 @@
+{
+  "extends": "../../tsconfig-base.json",
+
+  "compilerOptions": {
+    "declaration": true,
+    "outDir": "build"
+  },
+  "include": [
+    "src"
+  ]
+}

packages/tslint.json

@@ -0,0 +1,12 @@
+{
+  "extends": ["tslint:recommended", "tslint-react"],
+  "linterOptions": {
+    "exclude": [
+      "config/**/*.js",
+      "node_modules/**/*.ts"
+    ]
+  },
+  "rules": {
+    "quotemark": [ true, "single" ]
+  }
+}