Remove PHP requirement from the IBCM simulator

[50Wliu]

The branch name no longer makes sense, as I ended up ripping out all the PHP, haha :P.

Anyway...as JavaScript has a FileReader API, we can leverage that to do all the processing locally instead of requiring a server.

Some other changes I performed along the way:

• HTML files are now HTML5
• Printing now respects the CSS file
• Modernized the JavaScript code to not use sprintf (we have padStart and stuff like that now 😊)
  • This raises the requirement to browsers released 2018 and onwards

TODO

• [x] Get rid of eval (yikes)
• [x] Pretend to "load" the file when clicking Load, instead of loading it immediately
• [x] HTML/CSS modernization? There is absolutely no reason the simulator needs to have that many tables!
• [ ] Better solution to the watchdog timer (workers?)

[50Wliu]

Note: This was more of a fun experiment, so I won't be discouraged or anything if you don't end up merging it for Reasons, but it does work!

[aaronbloomfield]

I really like this, and plan to include it. But with the course just moving online, and there being less help available to the students as a result, I'm hesitant to change this right before the students are going to start on the lab. So I'll merge this in in a few weeks. Thanks for all your work on this!