Fix callback tests

The problem with

    it { should validate_presence_of(:token_read) }
    it { should validate_presence_of(:token_write) }
    it { should validate_uniqueness_of(:token_read) }
    it { should validate_uniqueness_of(:token_write) }

was that it calls the before_validation callback.
This resulted in token being set to something random,
which then resulted in the tests failing.
Add method that returns todays events