cleaned up back-end mturk timer code
cleaned up back-end mturk timer code

ProjectSidewalk/SidewalkWebpage,ProjectSidewalk/SidewalkWebpage,ProjectSidewalk/SidewalkWebpage,ProjectSidewalk/SidewalkWebpage,ProjectSidewalk/SidewalkWebpage,ProjectSidewalk/SidewalkWebpage