Look into improving dependency management for example tests

[frangio]

zos-lib/package.json

Line 7 in b8f1764

"test_examples": "npm run prepack && cd examples/complex && npm i && npm test",

As mentioned in #105 (comment):

I think this is a bit messy. That there is a script which is running npm install, because it has dependencies that are not covered by zos-lib's dependencies. This probably messes up with Travis' caching of dependencies and slows our build.