updated README

Author: sommersoft

README.rst

@@ -1,4 +1,4 @@
-Introduction
+Introduction
 ============
 
 .. image:: https://readthedocs.org/projects/adafruit-circuitpython-ht16k33/badge/?version=latest
@@ -15,9 +15,15 @@ It supports both 16x8 and 8x8 matrices, as well as 7- and 14-segment displays.
 Note this library is intended for Adafruit CircuitPython's API.  For a library
 compatible with MicroPython machine API see this library: https://github.com/adafruit/micropython-adafruit-ht16k33
 
-Installation
+Dependencies
 =============
-This driver depends on many other libraries! Please install it by downloading
+This driver depends on:
+
+* `Adafruit CircuitPython <https://github.com/adafruit/circuitpython>`_
+* `Bus Device <https://github.com/adafruit/Adafruit_CircuitPython_BusDevice>`_
+
+Please ensure all dependencies are available on the CircuitPython filesystem.
+This is easily achieved by downloading
 `the Adafruit library and driver bundle <https://github.com/adafruit/Adafruit_CircuitPython_Bundle>`_.
 
 Usage Example
@@ -65,10 +71,49 @@ Contributions are welcome! Please read our `Code of Conduct
 <https://github.com/adafruit/Adafruit_CircuitPython_HT16K33/blob/master/CODE_OF_CONDUCT.md>`_
 before contributing to help this project stay welcoming.
 
-API Reference
-=============
+Building locally
+================
+
+To build this library locally you'll need to install the
+`circuitpython-build-tools <https://github.com/adafruit/circuitpython-build-tools>`_ package.
+
+.. code-block:: shell
+
+    python3 -m venv .env
+    source .env/bin/activate
+    pip install circuitpython-build-tools
+
+Once installed, make sure you are in the virtual environment:
+
+.. code-block:: shell
+
+    source .env/bin/activate
+
+Then run the build:
+
+.. code-block:: shell
+
+    circuitpython-build-bundles --filename_prefix adafruit-circuitpython-ht16k33 --library_location .
+
+Sphinx documentation
+-----------------------
+
+Sphinx is used to build the documentation based on rST files and comments in the code. First,
+install dependencies (feel free to reuse the virtual environment from above):
+
+.. code-block:: shell
+
+    python3 -m venv .env
+    source .env/bin/activate
+    pip install Sphinx sphinx-rtd-theme
+
+Now, once you have the virtual environment activated:
+
+.. code-block:: shell
 
-.. toctree::
-    :maxdepth: 2
+    cd docs
+    sphinx-build -E -W -b html . _build/html
 
-    adafruit_ht16k33/index
+This will output the documentation to ``docs/_build/html``. Open the index.html in your browser to
+view them. It will also (due to -W) error out on any warning like Travis will. This is a good way to
+locally verify it will pass.