Filling out initial rubocop support for metadata.rb and the Gemfile.

https://blueprints.launchpad.net/openstack-chef/+spec/lint-and-unit-testing-for-havana
Removing tailor, cleaning up metadata and Gemfile, added TESTING.md and fixed a
broken test.

Addresses: blueprint rubocop-for-metering
Change-Id: I5a712c18033b6586548903dea93c8421050d971e
Merge "Filling out initial rubocop support for metadata.rb and the Gemfile."
Move to use "get_password" instead of "{user,service,db}_password"

The user_password, service_password and db_password functions are redundant
since they simply call "secret". Creates a get_password function thata will
accept a "type" of db, service or user.

All instances of these calls have been changed to call get_password

Change-Id: Ia4dbfe4ff794efc84c900950a666085deebaf7f3
Partial-Bug: #1195915