[FrontEnd] Removed display of java folder for admin user
[FrontEnd] Show alertDialog when script is selected
[FrontEnd] Added lcok icon
[FrontEnd] Display lock for locked script
[FrontEnd] Release lock when marks have been uploaded
[FrontEnd] Prevent the marking of a locked script
[FrontEnd] Check if someone has started marking a script before downloading files
[FrontEnd] Release lock when returning to test selection from marking screen