Add: install + editor config instructions

Author: superKalo

README.md

@@ -1 +1,13 @@
 # Common ground for the Ambire apps
+
+This package puts together the core business logic behind Ambire web and mobile apps.
+
+## Install
+
+```bash
+yarn install
+```
+
+## Editor Config
+
+Make sure your code editor has plugins that support the following configuration files: `.editorconfig`, `.prettierrc`, `tsconfig.json`, `eslintrc.js`, [`import-sorter.json`](https://github.com/SoominHan/import-sorter).