Added tests for next/prior to the Jamfile. Ported tests to lightweight_test.hpp.

test/Jamfile.v2

@@ -56,6 +56,7 @@ test-suite iterator
     [ run minimum_category.cpp ]
     [ compile-fail minimum_category_compile_fail.cpp ]
 
+    [ run next_prior_test.cpp ]
     [ run advance_test.cpp ]
     [ run distance_test.cpp ]
 ;