Integrated 712 in existing Master branch

We have integrated the E712 with the Master branch.
3 Major Functionalities:
1) Code review dashboard link should be visible for only coding assignments
2) Previously students were able to upload only zip files, our aim is to see if student is able to upload a text file.
3) Code reviewer should be able to comment on a set of lines, in response author can reply to the comments which he received