Added .gitignore file.
Added common project files.

Signed-off-by: Byron Sanchez <bfs5030@gmail.com>
Added standard Android project files.

The Android Manifest contains the overall structure of the app, declares
device compatbility and defines the necessary permissions to run the
app. The other files are used at build time.

Signed-off-by: Byron Sanchez <bfs5030@gmail.com>