Add a comment about MapReduce, and modify documentation strings to comply with PEP8
Add a comment about MapReduce, and modify documentation strings to comply with PEP8

swesterveld/udacity-nd004-p4-conference-organization-app,swesterveld/udacity-nd004-p4-conference-organization-app,swesterveld/udacity-nd004-p4-conference-organization-app