DST hour_of_day realign bugfix

[jakebrady5]

When using a rule with hour_of_day validations, and asking for occurrences on the day that DST skips forward, valid occurrences would be missed.

Adding the hour of day here was simply adding the hour to the start time, causing the result to pass an occurrence.

Using the spec example where the validation is set to the 19th hour of each day:

$ Time.local(2019, 3, 10, 0, 0, 0).in_time_zone('America/Denver') + 19.hours
=> Sun, 10 Mar 2019 20:00:00 MDT -06:00

For this situation, changing the TimeWrapper to use dst_adjust: true seems to be a clear choice. The specs did not contain any examples that were adversely affected by this change, but please let me know if anything comes to mind.

[pacso]

@jakebrady5 - could you update the changelog please?