Extend README.md

Add some documentation to the README.

Change-Id: I7e7411e98f1abace6634448b245e8a94d1ddcbeb
Reviewed-by: Marcus Tillmanns <marcus.tillmanns@qt.io>

README.md

@@ -1,3 +1,43 @@
-# vscode-qt-tools README
+# Qt Extension for Visual Studio Code
 
-This extension provides some useful tools for Qt development with Visual Studio Code.
+This extension provides support for developing Qt projects with Visual
+Studio Code.
+
+## Features
+
+- Detects the Qt installations provided by Qt's online installer.
+- Creates CMake kits for each Qt installation.
+- Provides debugging support for Qt's C++ types.
+- Provides support for various Qt-specific file formats.
+
+## Getting started
+
+After installing the extension, you're asked to register your Qt
+installation folder. You can also manually trigger this calling the
+_Qt: Register Qt Installation_ command. This will create CMake kits
+for each Qt version.
+
+Now, open a Qt CMake project and select one of the newly created kits
+with the command _CMake: Select a Kit_ and build the project with
+_CMake: Build_.
+
+To debug your program, select _Run and Debug_ in the side bar and
+create a `launch.json` file. Select _Add Configuration..._ and choose
+from the available _Qt: Debug..._ options, depending on your platform
+and toolchain.
+
+## Commands
+
+### Register Qt Installation
+
+Lets you select the folder where Qt has been installed using the Qt
+installer.
+
+### Open UI File in Qt Designer
+
+Opens the currently selected .ui file in Qt Designer.
+
+## License
+
+This extension can be licensed under the Qt Commercial License and the
+LGPL 3.0. See the text of both licenses [here](LICENSE).