add functionality for three sets of questions.

[molikd]

Taipan uses a build function to describe the form for image annotation, since we have three separate activities our app should have three tabs, one for each activity, and a set of questions for each tab, this means that the buildTaipan function will need to be updated to take three question sets, and each of those question sets should appear in their own tab. so:

buildTaipan function in R/buildTaipan.R gets updated for three sets of questions
corresponding inst/app/server.R and inst/app/ui.R are updated to accommodate three sets of questions in three tabs.