add angular-ui-bootstrap
add Deckhand::Configuration::ModelConfig

the top-level config class was starting to accumulate too many
model-specific methods
move angular controllers into their own file
add angular-ui-bootstrap templates
add underscore.js
support actions with arguments

DSL example:
  model Foo do
    action :bar, :form => true
  end

This will look for a “form class” Foo::Bar which includes
Deckhand::Form.

Deckhand::Form includes ActiveModel::Model and
ActiveModel::Validations, and adds an “input” keyword to specify
argument types and default values.

Form classes should implement the #execute method to perform the
desired action after validations pass.

The UI will present a modal dialog when the action button is clicked,
which will show errors if validations fail and perform the action
otherwise. After successful action the modal will close and the
acted-upon item will be refreshed.
bump version