implement constructor t_timedeltaFromSeconds.

src/libmtime_hl.f90

@@ -127,6 +127,10 @@ module mtime_hl
     MODULE PROCEDURE t_timedelta_assign_ms
   END INTERFACE t_timedeltaFromMilliseconds
 
+  INTERFACE t_timedeltaFromSeconds
+    MODULE PROCEDURE t_timedelta_assign_sec
+  END INTERFACE t_timedeltaFromSeconds
+
   INTERFACE OPERATOR(*)
     MODULE PROCEDURE t_timedelta_scalar_multiply_inv_long
     MODULE PROCEDURE t_timedelta_scalar_multiply_inv_int
@@ -358,6 +362,13 @@ contains
     call deallocatetimedelta(td_tmp)
   end function t_timedelta_assign_ms
 
+  ! constructor for integer seconds (integer)
+  !
+  TYPE(t_timedelta) FUNCTION t_timedelta_assign_sec(td_sec)
+    INTEGER, INTENT(in) :: td_sec
+    t_timedelta_assign_sec = t_timedelta_assign_ms(td_sec*1000)
+  END FUNCTION t_timedelta_assign_sec
+  
 
   LOGICAL FUNCTION t_timedelta_equal(this, td) 
     CLASS (t_timedelta),  INTENT(in) :: this