Rename instantiate! to build, no more raising in build, no saving in build, no seeding of aspects in build.

This reverts commit 1481056a.

This reverts commit fb70dc8c, reversing
changes made to 53fef63a.

Conflicts:

	pkg/fedora/diaspora-setup
	pkg/ubuntu/diaspora-setup
	public/stylesheets/sass/application.sass
	spec/models/user/attack_vectors_spec.rb

removed loop and hidden checkboxes from publisher.  hidden field passes single aspect id or :all to controller

RegistrationsController#create deals with validation errors. Username, email, password now required on sign-up.

Remove RegistrationsController#new (which just called super, so it's not necessary).