use simple "Registration" title
display base product name
remember the entered email and reg. code

and display it when going back

also make the input fields disabled when already registered during installation
added inline help text for registering input fields
use standard check boxes instead of MultiSelectionBox for addons
support only a single base product

(multiple base products do not make sense)
fixed exception
better cache addons

keep the addons even when restarting the module in the installation workflow
changes
code review fixes
Merge pull request #43 from yast/ui_redesign

UI redesign