Add "Powered by" advertisement to app --version

src/saturnin.sh.skel

     test -n "$SATURNIN_APP_CODENAME" \
      && echo -n " - $SATURNIN_APP_CODENAME"
     echo
+    echo -n "Powered by Saturnin (__MKIT_PROJ_TAGLINE__)"
+    echo -n " __MKIT_PROJ_VERSION__"
+    echo -n " - __MKIT_PROJ_CODENAME__"
+    echo
     return "$EXIT_OK"
 }