Fix %$ismember %rename predicate for members added via %extend

Bug reported was incorrect renaming of PHP built-in functions, such as
next. See PHPFN in phpkw.swg.

Add some tests for the %rename predicates.

Examples/test-suite/python/rename_predicates_runme.py

@@ -0,0 +1,35 @@
+from rename_predicates import *
+
+r = RenamePredicates(123)
+r.MF_member_function()
+r.MF_static_member_function()
+r.MF_extend_function_before()
+r.MF_extend_function_after()
+GF_global_function()
+
+if r.MV_member_variable != 123:
+  raise RuntimeError("variable wrong")
+r.MV_member_variable = 1234;
+if r.MV_member_variable != 1234:
+  raise RuntimeError("variable wrong")
+
+if cvar.RenamePredicates_MV_static_member_variable != 456:
+  raise RuntimeError("variable wrong")
+cvar.RenamePredicates_MV_static_member_variable = 4567;
+if cvar.RenamePredicates_MV_static_member_variable != 4567:
+  raise RuntimeError("variable wrong")
+
+if cvar.GV_global_variable != 789:
+  raise RuntimeError("variable wrong")
+cvar.GV_global_variable = 7890;
+if cvar.GV_global_variable != 7890:
+  raise RuntimeError("variable wrong")
+
+UC_UPPERCASE()
+LC_lowercase()
+TI_Title()
+FU_FirstUpperCase()
+FL_firstLowerCase()
+CA_CamelCase()
+LC_lowerCamelCase()
+UC_under_case_it()