Extract the debug path into a constant
Get non-minified assets output for production
Production assets are output into a build directory
Update the make clean command
Move bootstrap.js into scripts directory
Clean up the extension build script
Add a hassets.minify setting

This will pass JavaScript through uglifyjs and CSS through cleancss
filters when the flag is set to True. This allows us to bundle
non-minified code in the Firefox extension and minified code in
both production and the Chrome extension.
Do not minify production Firefox assets
Ensure frontend script directories are created
Update Karma config to use new file paths