Add options for COSTS and duration to auto_explain, and add tests

When Who What
2019-01-31 13:56:09 Daniel Gustafsson (d_gustafsson) Closed in commitfest 2019-01 with status: Rejected
2018-12-26 05:43:09 Michael Paquier (michael-kun) New status: Waiting on Author
2018-11-05 12:02:44 Daniel Gustafsson (d_gustafsson) Closed in commitfest 2018-11 with status: Moved to next CF
2018-10-30 10:55:31 Daniel Gustafsson (d_gustafsson) Changed authors to Daniel Gustafsson (d_gustafsson)
2018-10-30 10:55:22 Daniel Gustafsson (d_gustafsson) Attached mail thread CAPPfruyZh+snR2AdmutrA0B_caj=yWZkLqxUTZYNjJCaQ_wKQg@mail.gmail.com
2018-10-30 10:55:21 Daniel Gustafsson (d_gustafsson) Created patch record