MWEB-979 Watcher and server runner

@RafLeszczynski @hakubo Please check if workaround in `gulp/options/dev.js` is acceptable. It worked fine while smoke tested.
Blame @RafLeszczynski https://github.com/Wikia/interactive-maps/commit/48f3c6a080eb980a88319bcf883a84952f129d6c ;) Also it's cachebuster vs cache buster, no biggie. Should I change it?