Proposes some updates to JS lessons 1 and 2.

These are some changes I think would be good for JavaScript lessons 1 and 2. I'd like them to initiate a discussion, and hopefully evolve a bit in the process. :)
To me, it looks as if the line "Conditions work with ..." (194) should be moved lower, so it is just above "Strict equality", i.e. after the info on the if statement. As a minor comment, would a colon at the end be helpful (I know it didn't have one before).