Import BooleanMessage to conference.py in TODO 6.
Import BooleanMessage to conference.py in TODO 6.

davcs86/fullstack-nanodegree-conference-cloud-app,swesterveld/udacity-nd004-p4-conference-organization-app,kerrmarin/fwd-conference,kerrmarin/fwd-conference,bschmoker/paxmidwest,scottharman/Conference-Central,codingvirtual/fullstack-p4-conference,eldonuts/Udacity-FSND-P4-Conferences,kirklink/udacity-fullstack-p4,arizonatribe/app-engine-demo,davcs86/fullstack-nanodegree-conference-cloud-app,kirklink/udacity-fullstack-p4,arizonatribe/app-engine-demo,swesterveld/udacity-nd004-p4-conference-organization-app,kerrmarin/fwd-conference,bschmoker/paxmidwest,eldonuts/Udacity-FSND-P4-Conferences,codingvirtual/fullstack-p4-conference,arizonatribe/app-engine-demo,codingvirtual/fullstack-p4-conference,scottharman/Conference-Central,bschmoker/paxmidwest,kirklink/udacity-fullstack-p4,scottharman/Conference-Central,davcs86/fullstack-nanodegree-conference-cloud-app,eldonuts/Udacity-FSND-P4-Conferences,swesterveld/udacity-nd004-p4-conference-organization-app