message: Update Android building instructions on Windows
diff: @@ -6,11 +6,29 @@ In addition to the requirements for [building Filament on Windows](../BUILDING.m
  need the Android SDK and NDK. See [Getting Started with the
  NDK](https://developer.android.com/ndk/guides/) for detailed installation instructions.
  +You'll also need [Ninja 1.8](https://github.com/ninja-build/ninja/wiki/Pre-built-Ninja-packages) (or
  +more recent) and [Git for Windows](https://git-scm.com/download/win) to clone the repository and run
  +Bash scripts.
  +
  Ensure the `%ANDROID_HOME%` environment variable is set to your Android SDK installation location.
  On Windows, we require VS2019 for building the host tools. All of the following commands should be
  executed in a *Visual Studio x64 Native Tools Command Prompt for VS 2019*.
  +### A Note About Python 3
  +
  +Python 3 is required. If CMake errors because it cannot find Python 3:
  +
  +```
  +Could NOT find PythonInterp: Found unsuitable version "1.4", but required is at least "3"
  +```
  +
  +then add the following flag to the CMake invocations:
  +
  +```
  +-DPYTHON_EXECUTABLE:FILEPATH=\path\to\python3
  +```
  +
  ## Desktop Tools
  First, a few Filament tools need to be compiled for desktop.
  