Merge pull request #6 from brentru/pypi-setup

add install instructions to README, enable setup.py

Author: brentru

README.rst

@@ -16,6 +16,30 @@ Adafruit_CircuitPython_AzureIoT
 Access to `Microsoft Azure IoT <https://azure.microsoft.com/en-us/overview/iot/>`_ from a CircuitPython device. This library can perform device
 messaging services (cloud-to-device, device-to-cloud), device services, and job services.
 
+Installing from PyPI
+=====================
+On supported GNU/Linux systems like the Raspberry Pi, you can install the driver locally `from
+PyPI <https://pypi.org/project/adafruit-circuitpython-azureiot/>`_. To install for current user:
+
+.. code-block:: shell
+
+    pip3 install adafruit-circuitpython-azureiot
+
+To install system-wide (this may be required in some cases):
+
+.. code-block:: shell
+
+    sudo pip3 install adafruit-circuitpython-azureiot
+
+To install in a virtual environment in your current project:
+
+.. code-block:: shell
+
+    mkdir project-name && cd project-name
+    python3 -m venv .env
+    source .env/bin/activate
+    pip3 install adafruit-circuitpython-azureiot
+
 Dependencies
 =============
 This driver depends on: