users import our resource via the storage.googleapis.com domain, and rather
suggest they access our resources via the simpler https://code.getmdl.io/thing.
Nothing has changed about where the content lives, it's still stored in the
same GCS buckets as before so the old links keep working as before indefinitely.
Manually checked that each bumped dependency doesn't break anything we depend on.
This means bumping the minimum version of Node.js to 0.12 as gulp-autoprefixer and gulp-size requires Node.js 0.12. Doesn't matter though as this is used in a dev setting, so newer Node.js should be expected. This will just get worse, so no point in delaying it.
