Static attributes must be executed first because dynamic attributes might
rely on them. This is really important when using the :parent relationship.
Previous code didn't work fine in situations like this one:
Factory.define(:generic_user, :class => User) do |u|
u.email { |user| "#{user.name}@example.com }
end
Factory.define(:flavio, :parent => :generic_user) do |u|
u.name "flavio"
end
When building a :user object the previous code would have set the email
attribute and then the name attribute. This results in a user object with
an invalid email address: the 'name' attribute is yet not set while the
'email' attribute is evaluated.
Closes#159
