TST: Make test dates aligned with test data.
TST: Make test dates aligned with test data.

Move dates queried near beginning of test data so that the range of data
covered does not extend beyond the beginning of the range.
i.e. the windows were covering 2016-01-25, which had no test data generated.
(Does not matter for the calendar based rolls, but is needed for volume
based rolls.)

Also, make room for having the first roll to be a day before the first auto
close by moving the first contracts auto close date back a day.

In preparation for testing volume rolls.

quantopian/zipline,florentchandelier/zipline,bartosh/zipline,alphaBenj/zipline,quantopian/zipline,bartosh/zipline,alphaBenj/zipline,Scapogo/zipline,Scapogo/zipline,humdings/zipline,florentchandelier/zipline,humdings/zipline,enigmampc/catalyst,enigmampc/catalyst