Deprecate bypassSchema param, introduce updateOptions

[bhunjadi]

As reported in #15, bypassSchema parameter is not working.

I've taken here a different approach, you can now pass updateOptions object to cache config.

Instead of

Posts.cache({
  type:'one',
  collection:Meteor.users,
  fields:['username', 'profile.firstName', 'profile.lastName'],
  referenceField:'author_id',
  cacheField:'author',
  bypassSchema: true
})

we have

Posts.cache({
  type:'one',
  collection:Meteor.users,
  fields:['username', 'profile.firstName', 'profile.lastName'],
  referenceField:'author_id',
  cacheField:'author',
  updateOptions: {
    bypassCollection2: true
  }
})

which works as expected.

Other updates:

• cacheField transform can now return undefined without crashing, because Meteor changed the way undefined fields are handled in insert/update/find. See the docs
• bumped lodash version to 4.17.15
• updated testing - for easier testing of updateOptions which requires both aldeed:collection2 and simpl-schema packages

[StorytellerCZ]

@bhunjadi can you please resolve the conflicts. I will be happy to merge then.