Feature: Setup automated browser testing infrastructure

[TheNotary]

As Engineers, We need automated browser testing, For react-frontend, and pax-imperia-js That ensures our WebGL stuff is functioning fine That ensures our react specific logic is correct, and That ensures our websockets are talking ok, So we don't feel nervous about refactoring, feature additions, and bugs.

Stories

• [ ] #28
• [ ] #29
• [ ] #30
• [ ] #31

[TheNotary]

Some work was done in the testing space for react-frontend/ via #58. Specifically jest and react testing-library are used to run unit tests against userContext, and various other things, but nothing about the core js library or the canvas has been tested.