Log Message:
smake: update to 1.3nb3.

Switch to latest distfile.
Update provided by Michael Bäuerle via pkgsrc-wip.

Changelog
=========

Release 2019-02-18:
- smake (psmake): a missing link to libschily/strnlen.c has been added.

Release 2019-03-11:
- psmake: cpfiles/lnfiles/rmlinks now contain a line for the new
          include/schily/type_val.h