Clarify Enrollment Caption in Session Listing

[dartajax]

Here's how it is ...

It has the possibility of looking to a user that zero out of one options has been selected or chosen (0/1) - you have to go back and read to realize that the zero pertains to individual students selected (the count of those) and the one pertains to how many learner groups have been selected.

I would propose this might be clearer to a user ...

... so the user can tell oh yeah I have not selected any "Learners" - "Individual Learners" would be clearer here too but I have selected one learner group - and yet even weirder with ILM's the learner group count does not apply - those are both part of the discussion we may have on this - may result in future tickets or wontfix.