additions and grammer typo fix

I think it would be nice to add the chapter names in README of each chapter instead of just "Read it online here"

In this commit https://github.com/CamDavidsonPilon/Probabilistic-Programming-and-Bayesian-Methods-for-Hackers/commit/29bfc74d1dd43e6c14fd3c4f95c9a7ff8128ae8f

Instead of "visitors are *likely friendly* and affectionate in the former", I think its better to write "visitors are *likely to be more friendly* and affectionate in the former"