Rework results form as Vue components

[philipbelesky]

Basically the results form is very messy in its template logic, and uses a bunch of JS code and libraries that aren't used elsewhere. So this would primarily be a way of streamlining a lot of the validation code.

As part of this refactor it should allow for some of the more advanced methods such as side swapping as mentioned in #163. Going to handle this as part of this issue even if its a bit of an akward pairing.

• [x] Upgrade vue to 2.0 (#367)
• [x] Upgrade jquery to 3.0
• [ ] Convert form to vue components
• [ ] Reimplement id_choose_sides
• [ ] Remove jquery validation
• [ ] Remove enter_results.js

[philipbelesky]

This doesn't seem strictly necessary anymore, as basic validation methods seem to be working well in BP and side swapping is pretty niche. Will remove from the milestone but keep around in case we end up deprecating jquery or something that requires it to be redone.