test: add make-python-testenv.sh script

This scripts makes it easy to (re)create python testing environment.

scripts/make-python-testenv.sh

@@ -0,0 +1,21 @@
+#!/usr/bin/env bash
+#
+# Script to create or update a python development environment.
+# It rebuilds the core and bindings as needed.
+#
+# After running the script, you can either
+# run `pytest` directly with `env/bin/pytest python/`
+# or activate the environment with `. env/bin/activacte`
+# and run `pytest` from there.
+set -euo pipefail
+
+export DCC_RS_TARGET=debug
+export DCC_RS_DEV="$PWD"
+cargo build -p deltachat_ffi --features jsonrpc
+
+if test -d env; then
+	env/bin/pip install -e python --force-reinstall
+else
+	tox -e py --devenv env
+	env/bin/pip install --upgrade pip
+fi