Sandbox - Compiling: Create a branch with webpack for testing

[mejiaj]

Setting up a branch with webpack would help us debug and test USWDS issues faster.

Webpack specific issues reported so far:

• Can't seem to resolve "Error: Can't find stylesheet to import." when compiling with dart sass/webpack (ver. 3.3.0) uswds#5129
• USWDS - Bug: Cant compile Angular application after npm install uswds#5097