Add .Date/.DateTime coercers to Instant

src/core/Instant.pm

@@ -1,3 +1,5 @@
+my class Date { ... }
+my class DateTime { ... }
 my class Duration {... }
 
 my class Instant is Cool does Real {
@@ -52,6 +54,9 @@ my class Instant is Cool does Real {
     method Int   (Instant:D:) { $.tai.Int    }
     method narrow(Instant:D:) { $.tai.narrow }
 
+    method Date(Instant:D:)        { Date.new(self)         }
+    method DateTime(Instant:D: |c) { DateTime.new(self, |c) }
+
 #    TODO: should be the new .gist, probably
 #    method Str() {
 #        'Instant:' ~ default-formatter

src/core/Temporal.pm

@@ -1,6 +1,3 @@
-my class DateTime { ... }
-my class Date     { ... }
-
 my role Dateish {
     has Int $.year;
     has Int $.month = 1;