Fix generating command for childrens cartoon series on NRK

[olekang]

I just needed this for offline cartoons for the kid in the car. As such I only looked at those parts. Everything else might break horribly, this isn't pretty. (=

Thought the PR might be useful for people submitting bugs, and looking for solutions. So I'm submitting it anyway, for that purpose.

[stefansundin]

Thanks for the help! Really appreciate it!

I'll probably leave it like this until I get time to do some work on the extension. So don't worry that I'm not merging it right away. :)

[stefansundin]

This doesn't seem to be a problem, at least not anymore. It should have been working since e4ebe5ce98f68d4b83d8b0a521f442a357e6a4a9 (before this PR) but maybe there are some specific kids program that was matching the first regex (/^https?:\/\/(?:tv|radio)\.nrk\.no\.?\/(?:program|serie)[^A-Z]*\/([A-Z][A-Z0-9]+)/) which would have prevented the other function from running.

It seems like the new function works in all cases so I am removing the original matcher in the next version (52b43ece474da5cc79d29c7ba9de986d0dc55123).

As for the nicer filename which puts the season and episode numbers in the beginning of the filename, that is definitely a highly-requested feature which should probably be written to work with all sites at some point.