fixes latest round of comments, adds exception table, cleans up how to do recursive dep fetching
fixes latest round of comments, adds exception table,
cleans up how to do recursive dep fetching

CloudVLab/tools,googlecodelabs/tools,CloudVLab/tools,googlecodelabs/tools,chrisrecher/tools,Qwiklabs/codelab-tools,chrisrecher/tools,googlecodelabs/tools,Qwiklabs/codelab-tools,googlecodelabs/tools,Qwiklabs/codelab-tools,Qwiklabs/codelab-tools