Switches to use fork-ts-checker

Splits App into AppBase & AppWithConfigBase for impl of new webviews

Adds bundle analyzer
Adds circular deps analyzer
Switches to es2018 output
Removes many circular dependencies

Keeps all path manipulation on the host rather than guest
Fixes shared/local path munging for mac/windows
Keeps current user lookup local when a guest
Keeps difftool lookup local when a guest
Avoids fetch date lookup when a guest
Stops clearing node_modules (for now)

Enables source maps always
Minifies css
Removes unused plugins

Switches to use full source-map for better debugging (stepping)

Updates dependencies

Changes from out to dist
Adds size-plugin (commented out for now)
Adds image cache to improve bundle performance

Adds new webpack tree shaking plugin

Uses webpack for all of it

Consolidates ui dependencies & build into main

Uses import() for copy/paste and tmp

Adds webpack for bundling (disabled for now)
Uses tslib to bundle less duplicate code