Add test tasks and travis encryption
Override rake test when TestUnitRailtie doesn't exist
Don't redocument test tasks
Add db:test:prepare to db task
v0.0.5: Add `rake test` override.

Overrides `rake test` whenever Rails doesn't have its TestUnitRailtie
with the RSpec::Core::RakeTask and Teaspoon tasks, since that's what I
use for TDD.