v0.4

Reverted changes introduced in v0.3 because setting notifications to "Ask" when DND is off resulted in all exceptions being overridden and set to "Ask", even if a particular site had been set to "Allow" or "Block". This essentially broke the functionality of the extension. To fix, the notifications setting used when DND is off is once again "Allow All". I will have to experiment to see if it's possible to both use the "Ask" setting AND enforce exceptions.