Android 101 app

Description

Android 101 repo to teach how to develop an Android app.

Features

1. Hello World! sample (see branch hello_world and PRs #1 and #3).
2. Say Hi sample (see branch say_hi and PR #2).
3. Chuck Norris Jokes sample (see branch chuck_norris_jokes and PR #4).

TODOs

1. Save and restore variable state of Hello World! sample (see Recreating an Activity).
2. Save and restore variable state of Chuck Norris Jokes sample (see Fragments).
3. Support landscape devices (tablets) on Chuck Norris Jokes sample (see Building a Flexible UI).