Overhaul Toolchain

[jimmynotjim]

Update the very outdated toolchain with a relatively minimal set of tools. Direction so far:

• npm scripts for task running (may switch to Gulp if ends up painful)
• microbundle for file bundling/transpiling
• jest for testing
• eslint for linting and prettier fomatting

[jimmynotjim]

Really simple setup so far, but seems to be working well together. Time will tell once there's some real code to work with.

[jimmynotjim]

Done and working.