eliminate kludge

[DanGrayson]

trafficstars

	$(eval check-$i:; \
		if ! grep "CacheExampleOutput => true" @srcdir@/$i.m2 >/dev/null ;\
		then @pre_bindir@/M2 -q $(STOP) -e "needsPackage(\"$i\",LoadDocumentation=>true,DebuggingMode=>true); check($i,UserMode=>false); exit 0" ;\
		fi ))

Instead, check should take care of it, and print a warning message when checks are not done because optional components are not present.