v2 Enable local development (#52)

- Create local dev environment
- Add gas-client and google-apps-script-webpack-dev-server packages for development
- Add dev/ wrapper app
- Update webpack config to support development environment
- Redesigned READMEs
- Support typescript
- Update npm scripts
- Organize and update .gitignore file
- Add .vscode settings for clasp files
- Remove tracking for files in dist/

.gitignore

@@ -1,3 +1,16 @@
+# npm
 node_modules
+
+# clasp files
 .clasp*
-creds.json
+creds.json
+
+# certs
+*.pem
+certs/
+
+# build
+dist/
+
+# mac
+.DS_Store