Add CRUD helper routes

[sam]

Add short-cuts in Controller for CRUD helper routes:

class Example < Harbor::Application
  class Home < Harbor::Controller

    index do
      response.puts "Welcome home!"
    end

    show do |id|
      response.puts "You asked me to show #{id}"
    end

    update do |id|
      response.puts "Aight, stand back, I've got this! (#{id})"
    end

    delete do |id|
      response.puts "#{id} is going down!"
    end

  end # Controller: Home
end # Application: Example

Note:

• Fully implementing this is going to depend on issue #17
• I recommend putting this somewhere like lib/harbor/helpers/crud_routes.rb to keep them organized, and make them easy to document/reference for people learning the framework

[sam]

Added in 0d7cf4ae47f31cb7f1918b8d25a54151c80081f2.