Improve testing around require() features.

src/test/res/req/subsample.lua

@@ -0,0 +1,8 @@
+-- helper file for require() tests
+module( 'req.subsample', package.seeall )
+function h()
+	print 'in subsample.h' 
+end
+print 'loading subsample.lua'
+return 'return value from subsample', 'second return value from subsample'
+