Recycle preaggregations for different timezone when granularity is <= 1h

In order to use preaggregations with timezones we now need to specify in the configurations files a list of timezones for which cubejs generate the aggregations periodically. This makes sense when the granularity is larger than one hour, since the data might be different. However, when the granularity is one hour or less the UTC preaggregations could be used, just by shiftings the key by n-hours.