Add models, API query class, and buttons to do test queries.
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Add template for API keys file and notes to README
Merge pull request #3 from flibbertigibbet/feature/add-models

Add models, API query class, and buttons to do test queries.
Add RetroLambda to project and fix use of HomeFragment

App was skipping the use of HomeFragment entirely, called
the HomeActivity onGoButtonPressed directly via the onClick
xml attribute. When using a fragment with activity,
ensure the following:
  - Activity extends android.support.v4.app.FragmentActivity
  - XML fragment definition has the class attribute properly set
  - Your Activity uses the activty xml layout
Add java env setup instructions to README
Add attribution notes to VIPTabBarActivity TabsAdapter class
Move retrolambda plugin to app build.gradle