Use marionette.absolute_url() instead of manually concatenating
Get rid of the property_class hack in the puppeteer library
Add test_home_button.py; Add prefs lib to puppeteer
Refactor tests to use self.lib instead of self.puppeteer
Add a @uses_lib('name') convenience decorator for injecting libraries directly into test scope
Update README.md
POC test of shortcut commands using EventUtils via execute_script.