Merge pull request #1 from nickdotreid/pip

Added User Biography Fields
removed separate pronounced_name field; added column with comments; added bios controller to get output as TSV file
minor changes to bio form and model
updated message about logging in; don't allow access to instructor's page
minor changes to Debugging chapter
minor changes to Debugging chapter
Sequences chapter takes parts from strings and lists
small fixes to exercises in Sequences chapter
added boiler plate controllers for adding sections
added "sections" model to db
added foreign key to sections table into auth_user
added output for list of sections into section_list
added simple view for sections list
added list of users in a section to section update list
removed word edit from section title
added basic form to add user email addresses
got form to search for emails from list and then add users that are matched
added clear_users method to sections table
added way to clear sections
added way to delete section