New versions of dependencies & got rid of unneeded stuff

Immutable.Vector is now dense (https://github.com/facebook/immutable-js/commit/52073637c54c55c9c730155635363bf577198381),
so lots of new 'todo isnt undefined' checks, have to
figure out a better way.

- Replaced webpack with browserify
- Replaced gulp with npm scripts
- Replaced SCSS with LESS
- Deleted unnecessary bower components
- Refactored directory layout
- Now uses http-server for dev server instead of gulp based server
- Build is now included in repo