add filterString utility to regex utils
use namespace alias for boost::algorithm
initial work on slide quizzes
add username to presentation log
more permissive regex for capturing quiz items
refine === completion in r markdown
refinements to quiz feedback layout
add images to quiz feedback
refine quiz feedback ui
more tweaks to feedback region
change field name: correct -> answer
add threadsafe map class
more customizable session launch logic
improved scoping of supporting images for slides
factor child process reaping into it's own class
factor session process config into a helper function
allow custom session launch
create session launch profile object to wrqp launch parameters
session launch profile to/from json
move pam helper class to core namespace