Error when setting time parameter on track/track once events

    can't convert Symbol into Integer
    /Users/mglenn/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/klaviyo-0.9.4/lib/klaviyo/client.rb:34:in `[]='
    /Users/mglenn/.rbenv/versions/1.9.3-p327-perf/lib/ruby/gems/1.9.1/gems/klaviyo-0.9.4/lib/klaviyo/client.rb:34:in `track'

When setting a time for a track event, set the parameter before converting to a base64 encoded string.