get tests working on Python 3.13 and 3.14

…risha#139)

Python 3 removed the builtin execfile so this replaces it with read,
compile, and exec (see https://stackoverflow.com/questions/436198/).
Because this works in both Python 2 and Python 3, we use this
alternative unconditionally.

…iles

Makefile: do not install shared libraries with executable permissions

…file

Replace use of execfile removed in Python 3

Refresh pointers in parse_qsl(). Fixes grisha#144

On 32-bit systems, tp_hash expects Py_hash_t (int) not long,
causing a build failure due to incompatible pointer types.

Use Py_hash_t return type for table_nohash(). Fixes grisha#149