everything me app
Fix code review findings
wait for app to launch; use tap instead of click
pick up changes introduced by PR #1141
add wait for categories to be displayed
verify the last page from the home screen

Conflicts:

	gaiatest/tests/everythingme/test_everythingme_app_install.py
Merge branch 'everythingme_app'

Conflicts:
	gaiatest/tests/everythingme/test_everythingme_app_install.py