feat: bring back and adapt python bindings with rust core

* import python, try to adapt for rust

* add missing wrapper functions

* - try to write up how to build python bindings
- strike some unused functions from deltachat.h

* adjustments to make tox work

* try to run circle-ci with python build

* don't do docs

* running cargo test as well

* don't run cargo test anymore, that's done in other ci jobs

* also build docs

* don't run doxygen anymore

* subst C with Rust

* a try to get better wheels

Closes #41

ci_scripts/README.md

@@ -0,0 +1,52 @@
+
+# Continuous Integration Scripts for Delta Chat
+
+Continuous Integration is run through CircleCI
+but is largely independent of it. 
+
+
+## Generating docker containers for performing build step work 
+
+All tests, docs and wheel building is run in docker containers:
+
+- **coredeps/Dockerfile** specifies an image that contains all 
+  of Delta Chat's core dependencies as linkable libraries. 
+  It also serves to run python tests and build wheels 
+  (binary packages for Python). 
+
+- **doxygen/Dockerfile** specifies an image that contains
+  the doxygen tool which is used to generate C-docs. 
+
+To run tests locally you can pull existing images from "docker.io",
+the hub for sharing Docker images::
+
+    docker pull deltachat/coredeps
+    docker pull deltachat/doxygen 
+
+or you can build the docker images yourself locally
+to avoid the relatively large download:: 
+ 
+    cd ci_scripts  # where all CI things are 
+    docker build -t deltachat/coredeps docker-coredeps
+    docker build -t deltachat/doxygen docker-doxygen 
+
+## ci_run.sh (main entrypoint called by circle-ci)
+
+Once you have the docker images available 
+you can run python testing, documentation generation 
+and building binary wheels:: 
+
+    sh DOCS=1 TESTS=1 ci_scripts/ci_run.sh 
+    
+## ci_upload.sh (uploading artifacts on success) 
+
+- python docs to `https://py.delta.chat/_unofficial_unreleased_docs/<BRANCH>`
+
+- doxygen docs to `https://c.delta.chat/_unofficial_unreleased_docs/<BRANCH>`
+
+- python wheels to `https://m.devpi.net/dc/<BRANCH>`
+  so that you install fully self-contained wheels like this:
+  `pip install -U -i https://m.devpi.net/dc/<BRANCH> deltachat`
+
+
+