Add help tokens: cohort courses & content libraries

[catong]

@mhoeber @andy-armstrong @marcotuts FYI. Updating config.ini to add help tokens for cohorted courseware and content libraries.
This PR adds 2 new help tokens, does not change any existing help tokens.

[mhoeber]

👍 I'm good with this. Want to confirm with @smagoun that this will make it's way to Saudi instance.

[catong]

@mhoeber are you saying that you want me to wait until we confirm with @smagoun ?

[mhoeber]

@catong no, don't need to wait as there's no downside to merging this. just still want confirmation of saudi implementation.

If you want to go, I'll merge after tests complete.

[catong]

@mhoeber it's OK. I'll do it; will check on it from home.

[smagoun]

@mhoeber @catong OK to merge - thanks! These should go into master so that other instances of Open edX can take advantage of them.

[mhoeber]

@smagoun merging, thanks. We'll need these for Birch release. Concern was more about getting to Saudi specifically before Birch is released