Moved js-yaml to dependencies.
Moved js-yaml to dependencies.

The index.js script which imports our eslint configuration requires
that js-yaml be accessible, however it was not included in the
project's dependencies. This moves it from devDependencies (installed
during packaging) to dependencies (installed always).

Change-Id: I7f7b0967b86f5312f5801fb4dbfbe72a453583aa

openstack/eslint-config-openstack