Add docs.

Signed-off-by: jinwei.fan <jinwei.fan@samsung.com>
Change-Id: I156163b1e68b48cab4f775e354d7bef68fd613fd

docs/developers-guide.rst

@@ -0,0 +1,58 @@
+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. SPDX-License-Identifier: CC-BY-4.0
+.. Copyright (C) 2020 AT&T Intellectual Property
+
+
+Developers Guide
+=================
+
+.. contents::
+   :depth: 3
+   :local:
+
+
+Version bumping the Xapp
+------------------------
+
+This project follows semver. When changes are made, update the version strings in:
+
+#. ``container-tag.yaml``
+#. ``docs/release-notes.rst``
+#. ``setup.py``
+#. ``xapp-descriptor/config.json``
+
+
+Testing RMR Healthcheck
+-----------------------
+The following instructions should deploy the QP Driver container in bare docker, and allow you
+to test that the RMR healthcheck is working.
+
+::
+
+    docker build -t qpd:latest -f  Dockerfile .
+    docker run -d --net=host -e USE_FAKE_SDL=1 qpd:latest
+    docker exec -it CONTAINER_ID /usr/local/bin/rmr_probe -h 127.0.0.1:4560
+
+
+Unit Testing
+------------
+
+Running the unit tests requires the python packages ``tox`` and ``pytest``.
+
+The RMR library is also required during unit tests. If running directly from tox
+(outside a Docker container), install RMR according to its instructions.
+
+Upon completion, view the test coverage like this:
+
+::
+
+   tox
+   open htmlcov/index.html
+
+Alternatively, if you cannot install RMR locally, you can run the unit
+tests in Docker. This is somewhat less nice because you don't get the
+pretty HTML report on coverage.
+
+::
+
+   docker build  --no-cache -f Dockerfile-Unit-Test .