Merge pull request #696 from AvadootNachankar/mongokit

Bug fix: Inconsistent/Invalid structure of instances of classes used for map-reducing
changes in models.py;

1. partially documented: couldn't complete a single file models.py, tells us the status of documentation in the project.
2. commented unusued variables
3. removed imports that are never used
Correction to the last commit: an incorrect models.py file submitted by mistake. this was the intended file. Sorry for the trouble. Maintaining too many branches :-(
Code added for displaying timestamp in log-files when this script is used.
New widget for email field & mandatory check added for upload-file widget.
Foundation's data-abide feature applied on click of each tab's Next button & Additional check imposed on college's drop-down.
Foundation's data-abide feature applied on click of each tab's Next button.