Build: Don't assume the browser environment; smoke test on Node w/ jsdom

Fixes gh-1950
I'd prefer to use the build/dist/test pattern that we have in other projects (e.g., [sizzle](https://github.com/jquery/sizzle/blob/061236ee6eb9f464d354dcba1356727411a5608d/Gruntfile.js#L268), [qunit](https://github.com/jquery/qunit/blob/a0604169c1919cf4ac7051e7ed7d65cb244c6d0d/Gruntfile.js#L221)). In other words, `…, "dist:*", "node-smoke-test", "compare_size"`, or better still, moving "node-smoke-test" into a "test" task.