Fix test fixture patching and move all fixture to json

[dinoboff]

Most fixture data should be defined in "test/fixtures.json", with its data used
to set the default firebase data for a test.

Your tests should reset the firebase before running, using
test/utils.js#setFirebaseData(somePatchToBaseData). e.g:

const utils = require('./utils.js');

describe('events', function() {

  beforeEach(function() {
    utils.setFirebaseData();
  });

});

To retrieve fixture data, you can use test/utils.js#fixtures(somePath); e.g.:

const utils = require('./utils.js');

describe('auth', function() {
  let chris;

  beforeEach(function() {
    chris = utils.fixtures('auth/users/google:chris');

    // set the database with chris not registered
    utils.setFirebaseData({
      auth: {
        publicIds: {chris: undefined},
        usedPublicIds: {chris: undefined},
        users: {'google:chris': undefined}
      }
    });
  });

  it('should let a user register', function() {
    // todo
  })

});

Returned values cannot be corrupted by a previous test and will always reflect
the data set in "tests/fixtures.json".

You can use test/utils.js#auth to authenticate with one of the fixture
registered users:

• auth.admin (admin);
• auth.chris alias for auth.admin;
• auth.alice (premium, can create event and has an "alice-event" event setup);
• auth.bob (participant of "alice-event" event);
• auth.emma (only registered - to test non-participant access to event).

They can used with targaryen tests:

expect(utils.auth.chris).can.read.path('classMentors/events');

Thoses object cannot be corrupted by previous tests.

[coveralls]

Changes Unknown when pulling a9902e0 on dinoboff:refine-rules-test into * on singpath:master*.

[dinoboff]

@SingaporeClouds I added the rules tests to travis and to make travis setup faster, I merged the rules package.json with the main one.

To test the rules:

npm run test:rules

or with mocha installed globally:

npm install -g mocha
cd database/
mocha