README: Add instructions for setting up a development environment.

README.md

@@ -8,3 +8,37 @@ This repository contains the source code for Zulip's PyPI packages:
   for Zulip's bots and bots API.
 * `zulip_botserver`: [PyPI package](https://pypi.python.org/pypi/zulip-botserver)
   for Zulip's Flask bot server.
+
+## Development
+
+1. Fork and clone the Git repo:
+   `git clone https://github.com/<your_username>/python-zulip-api.git`
+
+2. Make sure you have [pip](https://pip.pypa.io/en/stable/installing/)
+   and [virtualenv](https://virtualenv.pypa.io/en/stable/installation/)
+   installed.
+
+3. `cd` into the repository cloned earlier:
+   `cd python-zulip-api`
+
+4. Run:
+   ```
+   ./tools/provision
+   source ./zulip-api-py2-venv/bin/activate
+   ```
+
+5. You should now be able to run all the tests within this virtualenv.
+
+### Running tests
+
+You can run the tests for the `zulip_bots` package by typing:
+
+`./tools/test-bots`
+
+You can run the tests for the `zulip_botserver` by typing:
+
+`python -m unittest discover -v ./zulip_botserver`
+
+To run the linter, type:
+
+`./tools/lint`