Build docs using sphinx (#53)

Makefile

@@ -0,0 +1,20 @@
+# Minimal makefile for Sphinx documentation
+#
+
+# You can set these variables from the command line.
+SPHINXOPTS    =
+SPHINXBUILD   = sphinx-build
+SPHINXPROJ    = OPENCENSUS
+SOURCEDIR     = docs
+BUILDDIR      = docs/build
+
+# Put it first so that "make" without argument is like "make help".
+help:
+	@$(SPHINXBUILD) -M help "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)
+
+.PHONY: help Makefile
+
+# Catch-all target: route all unknown targets to Sphinx using the new
+# "make mode" option.  $(O) is meant as a shortcut for $(SPHINXOPTS).
+%: Makefile
+	@$(SPHINXBUILD) -M $@ "$(SOURCEDIR)" "$(BUILDDIR)" $(SPHINXOPTS) $(O)

docs/_sources/index.rst.txt

@@ -0,0 +1,26 @@
+.. OPENCENSUS documentation master file, created by
+   sphinx-quickstart on Mon Oct 30 12:42:31 2017.
+   You can adapt this file completely to your liking, but it should at least
+   contain the root `toctree` directive.
+
+Welcome to OPENCENSUS's documentation!
+======================================
+
+.. toctree::
+   :maxdepth: 2
+   :hidden:
+
+   trace/usage
+
+Getting started
+---------------
+
+The ``opencensus`` library is ``pip`` install-able:
+
+.. code-block:: console
+
+    $ pip install opencensus
+
+Fore more information on setting up your Python development environment, such as installing ``pip`` on your system, please refer to `Python Development Environment Setup Guide`_ for Google Cloud Platform.
+
+.. _Python Development Environment Setup Guide: https://cloud.google.com/python/setup