change .before('insert' to .before.insert for Meteor collections

- this is needed due to a change in meteor-collection-hooks starting
  with 0.4.0 which changed the 'before' from a single function to an
  object holding separate functions for insert/update/remove/fetch

- https://github.com/matb33/meteor-collection-hooks/commit/4d979d974495f0cf86ae073aca0e77167a649ed5