Minor typo fixes to tutorials.yaml
Merge pull request #1110 from html5rocks/even-more-observe

Minor typo fixes to tutorials.yaml
Adding in Vivian as an Author
Adding vivian image
Compresses a lot of the images re: #1104
Merge pull request #1111 from html5rocks/master

Adding Vivian.  Merging Addy's changes.  Compresses images.