dtg (rubygems): A DTG is a DateTimeGroup which is used in the military to save time.  DTG                        are saved in the format DDHHMML MMM YY, where D is day, H is hour, L is                        letter, M is month, and Y is year.  The Month is the 3 character                        representation such as JAN for January, MAY for May, DEC for December and so                        on.  Year is only the last two digits of the year e.g. 2019 is just 19.  The                        letter is the zone code such as W for whiskey which is HST, Z for zulu which                        is GMT, A-Z are the zones used.
Keywords: activesupport|date|date-time-conversion|date-time-formatting|date-time-group|datetime|dtg|dtg-formats|dtg-printing|dtg-zones|maritime-zones|nautical-zones|rails|rails-gem|ruby|ruby-gem|rubygem|time|timewithzone|timezone-conversion