Data Analysis and UI Refinements

- Removed border on progress bar at top of lecturer pages
- fixed "remember password" checkbox on sign-in page (grey was too
light)
- Included a check flag in lec_post_ques.js to prevent RESULTS RESET and
progressbar changes in the quiz sessions (check flag checks whether the
current question has been locked by the lecturer)
- Similarly altered the student php files to block updates to the
database when question is locked.
- Added some image resources that jQueryUI asks for (slows down pages on
initial run if files aren't included)
- Created PHP files to both check and update the status of the
question's lock bit