Change in default behaviour wrapping C++ bool for Python.

Only a Python True or False will now work for C++ bool parameters.
This fixes overloading bool with other types.

Examples/test-suite/overload_bool.i

@@ -0,0 +1,19 @@
+%module overload_bool
+
+%inline %{
+const char* overloaded(bool value) { return "bool"; }
+const char* overloaded(int value) { return "int"; }
+const char* overloaded(const char *value) { return "string"; }
+
+const char* boolfunction(bool value) { return value ? "true" : "false"; }
+const char* intfunction(int value) { return "int"; }
+
+
+// Const references
+const char* overloaded_ref(bool const& value) { return "bool"; }
+const char* overloaded_ref(int const& value) { return "int"; }
+const char* overloaded_ref(const char *value) { return "string"; }
+
+const char* boolfunction_ref(bool const& value) { return value ? "true" : "false"; }
+const char* intfunction_ref(int const& value) { return "int"; }
+%}