Create time Package for Shared/timeutil, mclock and slotutil (#9594)

* add time pkg

* Go fmt

time/utils.go

@@ -0,0 +1,21 @@
+// Package timeutils is a wrapper around the go standard time library.
+package time
+
+import (
+	"time"
+)
+
+// Since returns the duration since t.
+func Since(t time.Time) time.Duration {
+	return Now().Sub(t)
+}
+
+// Until returns the duration until t.
+func Until(t time.Time) time.Duration {
+	return t.Sub(Now())
+}
+
+// Now returns the current local time.
+func Now() time.Time {
+	return time.Now()
+}