Write "Getting Started" documentation for Android

Since the process of getting Qt for Android to work requires some insight into the system, we need to have a clear getting started guide for working with the port.

This should have:
1. Getting the Android NDK and SDK and setting up Qt Creator afterwards.
2. Creating a new Qt Quick 2 project with the wizard (explaining how QML files are installed to assets)
3. Creating a new Qt Quick 2 project using qrc to deploy QML files.
4. Setting up a kit for an existing project.
5. Limitations of the port currently.
6. Special considerations (menus, back button, etc.)