asylum: Debian repository page update

Instead of syslog-ng and syslog-ng-devel, have those two as symbolic
names, and syslog-ng-3.3 and syslog-ng-3.4 aswell. As a side effect,
the syslog-ng versions cannot be mixed anymore, one has to select one
version.

Signed-off-by: Gergely Nagy <algernon@balabit.hu>
asylum: Remove a debugging console.log from sources.list.js

Signed-off-by: Gergely Nagy <algernon@balabit.hu>
asylum: Improve the component selection

When selecting an invalid component combination, show an alert box at
the bottom. Also disable invalid component combos on every change.

Signed-off-by: Gergely Nagy <algernon@balabit.hu>