.travis.install-deps: only install QuickCheck2 when required
thyme.cabal: work around Data.ByteString{.Lazy,}.Builder rename in bytestring-0.10.2.0
Data.Thyme.Clock.UTC.UTCTime: bit-packed day&dt ↦ NominalDiffTime from MJD epoch

∙ Simplifies instance AffineSpace massively; no view/review required.
∙ View utcTime potentially a bit more expensive: divMod vs bit unpacking.
∙ OTOH review utcTime no longer requires a divMod.
∙ Data.Thyme.Clock.POSIX is now almost trivial.
Data.Thyme.Clock: UniversalTime
Data.Thyme.Clock: merge .Scale and .UTC ↦ .Internal
Data.Thyme.Clock.TAI: AbsoluteTime
Data.Thyme.Format: dubious instance {Format,Parse}Time {Universal,Absolute}Time

∙ As long as you know what you're doing…
Data.Thyme.Calendar.WeekdayOfMonth: n-th weekday of month
Data.Thyme.Calendar.WeekDate: documentation cleanup
Data.Thyme.Calendar.Internal.ordinalDate: div & mod ↦ divMod
Data.Thyme.Calendar.MonthDay: monthDayToDayOfYearValid ↦ monthDayValid
Data.Thyme.Calendar: addGregorian{Months,Years}{Clip,Rollover}
Data.Thyme.Format: readTime for lazy people
Data.Thyme.Clock: why not microsecondsToNominalDiffTime?
Data.Thyme.Time: time ↔ thyme conversion
Data.Thyme.LocalTime: midnight and midday
Data.Thyme.Calendar: type {Years,Months,Days} = Int
Data.Thyme.LocalTime: rename timeOfDayFraction ↦ dayFraction; swap direction
Data.Thyme.Time: wrappers for things that we do differently