This updates the Registration step as per recent mocks.
There is now only one checkbox which switches between (register everything now / register later). When the checkbox is not checked "register later" option gets selected, activation key dropdown gets disabled and information about activation keys is hidden to support the fact that no activation key will be used.
When the checkbox is checked it either loads previously used activation key in the case of "on edit" scenario, looks for a recently used activation key in localStorage or in a case there are no activationKeys automatically creates and selects one.
The Next button gets disabled only when "register-now" is selected, but there is no activationKey selected. As the option to clear the dropdown got removed this should occur only when fetching/creating activation key.
