Some formatting issues

Fixes the remaining comments made by @creighton in issue https://github.com/adlnet/xAPI-Spec/issues/311 except for the ones separated out into https://github.com/adlnet/xAPI-Spec/issues/370 and possibly other open issues. 

If/when this is merged, I suggest that  https://github.com/adlnet/xAPI-Spec/issues/311 can be closed. 

I would be __very__ surprised if anybody objects to any of the changes I've made here and suggest merging asap.