patch 8.0.0368: not all options are tested with a range of values

Problem:    Not all options are tested with a range of values.
Solution:   Generate a test script from the source code.
diff --git a/src/Makefile b/src/Makefile
index 5ed8362..09adb9a 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -2025,6 +2025,7 @@
 #
 scripttests:
 	$(MAKE) -f Makefile $(VIMTARGET)
+	$(MAKE) -f Makefile testdir/opt_test.vim
 	if test -n "$(MAKEMO)" -a -f $(PODIR)/Makefile; then \
 		cd $(PODIR); $(MAKE) -f Makefile check VIM=../$(VIMTARGET); \
 	fi
@@ -2033,6 +2034,8 @@
 	fi
 	cd testdir; $(MAKE) -f Makefile $(GUI_TESTTARGET) VIMPROG=../$(VIMTARGET) $(GUI_TESTARG) SCRIPTSOURCE=../$(SCRIPTSOURCE)
 
+testdir/opt_test.vim: option.c gen_opt_test.vim
+	./$(VIMTARGET) -u gen_opt_test.vim --noplugin --not-a-term
 
 # Run the tests with the GUI.  Assumes vim/gvim was already built
 testgui:
@@ -2753,6 +2756,7 @@
 	-rm -f *.o objects/* core $(VIMTARGET).core $(VIMTARGET) vim xxd/*.o
 	-rm -f $(TOOLS) auto/osdef.h auto/pathdef.c auto/if_perl.c auto/gui_gtk_gresources.c auto/gui_gtk_gresources.h
 	-rm -f conftest* *~ auto/link.sed
+	-rm -f testdir/opt_test.vim
 	-rm -f $(UNITTEST_TARGETS)
 	-rm -f runtime pixmaps
 	-rm -rf $(APPDIR)
@@ -2767,7 +2771,7 @@
 
 shadow:	runtime pixmaps
 	mkdir $(SHADOWDIR)
-	cd $(SHADOWDIR); ln -s ../*.[chm] ../*.in ../*.sh ../*.xs ../*.xbm ../gui_gtk_res.xml ../toolcheck ../proto ../vimtutor ../gvimtutor ../mkinstalldirs .
+	cd $(SHADOWDIR); ln -s ../*.[chm] ../*.in ../*.vim ../*.sh ../*.xs ../*.xbm ../gui_gtk_res.xml ../toolcheck ../proto ../vimtutor ../gvimtutor ../mkinstalldirs .
 	mkdir $(SHADOWDIR)/auto
 	cd $(SHADOWDIR)/auto; ln -s ../../auto/configure .
 	mkdir $(SHADOWDIR)/po