[S32/Temporal] spec DateTime.delta and Date.delta
[S32/Temporal] spec DateTime.delta and Date.delta

Clarify the .truncated-to method as well; it also uses the
C<TimeUnit> enum, instead of named parameters.

perl6/specs,prammer/specs,prammer/specs,prammer/specs,tokuhirom/specs,tokuhirom/specs,tokuhirom/specs,perl6/specs