Make it easier to run a single person

[benjamin051000]

Sometimes students make multiple submissions that look like this:

1. zip with source code
2. Non-zip (PDF, or something else)
   ...

It becomes incredibly difficult to grade just that one person, since the program unzips the primary .zip, and immediately reads the unzipped contents.

Possible solutions

• Perhaps a flag like --pause-after-unzip would be useful to give us time to swap out the VHDL files... Although this could get really hairy depending on when the paths for the source code are found.
• An ability to skip the unzip stage altogether. I like this one better, since it makes more intuitive sense, and it's typically only a problem with one or two students anyway. Maybe there's a mode that just traverses the submissions dir and creates a StudentData object for whatever it finds.

[benjamin051000]

The case where students submit multiple times includes one submission before the deadline, with potentially unfinished code; and another submission after the deadline, with modified contents. Being able to pick which one you want in Speedgrader, download it, and simply run it on its own would be really nice.

[benjamin051000]

This honestly could just be a simple function that replaces the normal unzip operation. This would actually be pretty easy to implement.