Adding a way to access an Atom Entry field

if I had a member declared like this:

    member.values do |value|
      value.id app.id
      value.title app.name
      value.updated_at app.updated_at.utc
      value.state app.state
      value.description app.description
      value.price app.price
    end

I couldn't access fields such as "description", "price", etc. So I added a method_missing to the base Xml class of the Atom representation so I can do:

entry.description
#=> "Foo"
entry.price
#=> "10.0"

Patch: http://github.com/akitaonrails/restfulie/commit/430c9031b7e84f33904...