Use more compatible hashbangs

This adds a #! line to the top of setup.py, because it is a script
with the executable bit set. Although neither recent nor current
documentation in the project recommends to run "./setup.py", this
should probably have the intuitive effect of attempting to run the
script with a Python interpreter rather than a Unix-style shell.

It also uses the "env trick" in init-tests-after-clone.sh so that
script runs with whatever bash interpreter is found in a normal
PATH search. While "sh" is expected to be found in /bin on all
Unix-like systems, that is not always the case for "bash". This
change slightly improves compatibility by supporting systems that
don't ship with bash but on which it has been installed.

Author: EliahKagan

init-tests-after-clone.sh

@@ -1,7 +1,9 @@
-#!/bin/bash -e
+#!/usr/bin/env bash
+
+set -e
 
 if [[ -z "$TRAVIS" ]]; then
-  read -p "This operation will destroy locally modified files. Continue ? [N/y]: " answer
+  read -rp "This operation will destroy locally modified files. Continue ? [N/y]: " answer
   if [[ ! $answer =~ [yY] ]]; then
     exit 2
   fi
@@ -13,4 +15,4 @@ git reset --hard HEAD~1
 git reset --hard HEAD~1
 git reset --hard HEAD~1
 git reset --hard __testing_point__
-git submodule update --init --recursive
+git submodule update --init --recursive

setup.py

@@ -1,3 +1,5 @@
+#!/usr/bin/env python
+
 from typing import Sequence
 from setuptools import setup, find_packages
 from setuptools.command.build_py import build_py as _build_py