pyosys: fix regressions from 0.58

- consistently use value semantics for objects passed along FFI boundary
  (not ideal but matches previous behavior)
- add new overload of RTLIL::Module: addMemory that does not require a "donor" object
  - the idea is `Module`, `Memory`, `Wire`, `Cell` and `Process` cannot be directly constructed in Python and can only be added to the existing memory hierarchy in `Design` using the `add` methods - `Memory` requiring a donor object was the odd one out here
- fix superclass member wrapping only looking at direct superclass for inheritance instead of recursively checking superclasses
- fix superclass member wrapping not using superclass's denylists
- fix Design's `__str__` function not returning a string
- fix the generator crashing if there's any `std::function` in a header
- misc: add a crude `__repr__` based on `__str__`

pyosys/wrappers_tpl.cc

@@ -21,6 +21,12 @@
 // <!-- generated includes -->
 #include <pybind11/pybind11.h>
 #include <pybind11/native_enum.h>
+#include <pybind11/functional.h>
+
+// duplicates for LSPs
+#include "kernel/register.h"
+#include "kernel/yosys_common.h"
+
 #include "pyosys/hashlib.h"
 
 namespace py = pybind11;
@@ -28,7 +34,7 @@ namespace py = pybind11;
 USING_YOSYS_NAMESPACE
 
 using std::set;
-using std::regex;
+using std::function;
 using std::ostream;
 using namespace RTLIL;