Improved error handling for struct types

lib/time/time.q

@@ -7,7 +7,7 @@ sleep(nanoseconds Int) {
 		seconds, nanoseconds = nanoseconds / 1000000000
 	}
 
-	duration := new(timespec)
+	duration := new(sys.timespec)
 	duration.seconds = seconds
 	duration.nanoseconds = nanoseconds
 	sys.nanosleep(duration)

lib/time/timespec.q

@@ -1,4 +0,0 @@
-struct timespec {
-	seconds Int
-	nanoseconds Int
-}