Upstream CJS require and typings for GuavaJS

[rzhw]

We're currently using a custom CommonJS wrapper and ambient typings for the guava-js bower package. The wrapper is a series of eval("[...]/node_modules/guava-js/[...].js") statements(!).

It'd be nice to either remove or replace this dependency, obsoleting this issue, or switch to an npm-published version of guava-js that can be loaded like any other regular Node.js module.