update main readme

Author: F4r3n

README.md

@@ -1,4 +1,27 @@
 # 4D Analyzer
 
-This VS Code extension provides support for the **[4D](https://www.4d.com/)** language.
-It is published in the [Visual Studio Marketplace](https://marketplace.visualstudio.com/items?itemName=4D.4d-analyzer).
+This extension provides support for the 4D language in VSCode.
+
+## Installation
+
+In the `editor` folder:
+```
+npm i
+npm run compile
+```
+
+## Launch
+
+This extension can be launched in 2 different modes:
+* **Launch Extension Debug** launches the extension and listen to the port 1800 without launching the 4D application.
+* **Launch Extension** launches the extension and the 4D application.
+
+## Quick Links
+
+* Marketplace VSCode: https://marketplace.visualstudio.com/items?itemName=4D.4d-analyzer
+* Doc 4D: http://developer.4d.com/docs/
+
+## License
+
+See the [LICENSE](LICENSE.md) file for details
+