Change the mock minute data to no longer use an increasing arange, so
that a days worth of minute data can be summed and fit inside of a
uint32.
This change was required because of working on new test data that looked
like [0, 100, 200, 0, ] which was resulting in a daily rollup of 0 data,
when the coverage needed a non-0 value.
Also, factor out the resampling function, with an eye on a making it
easier to convert from minute bars to daily bars during ingest/load
processes.
Eddie Hebert