Extend project metadata for better display in PyPI

Author: matthewwardrop

setup.py

@@ -1,3 +1,31 @@
+"""
+Mensor is a graph-based computation engine for computing measures and metrics.
+It:
+
+- defines a new grammar for extracting measures and metrics that is designed to
+  be intuitive and capable (it can do almost(?) anything that makes sense to
+  do with metrics and measures).
+- makes measure and metric definitions explicit and shareable, and their
+  computations transparent and reproducible.
+- allows multiple data sources to be stitched together on the fly without users
+  having to explicitly write the code / query required to join the data sources.
+- is agnostic as to how data is stored or accessed, and new data backends are
+  relatively simple to write.
+- allows for local ad-hoc definitions of additional data sources for exploration
+  by data scientists or other technically minded folk, decoupling it from
+  deployment into production services.
+
+**Note:** Mensor is currently still under heavy development, and intrusive
+changes to the API are expected. To minimise the impact on downstream projects,
+Mensor will strictly adhere to semantic versioning. In particular, any
+incompatible or sufficiently adventurous change to classes expected to be used
+outside of Mensor itself will resulting a major version bump. If you pin the
+version of Mensor used in your project using `mensor>=x.y(.z)?<x.y+1`
+(e.g. `mensor>=0.1.2<0.2`), you should be protected from any code churn and can
+upgrade to newer versions of Mensor after reading the release notes at your
+leisure.
+"""
+
 from setuptools import find_packages, setup
 
 version_info = {}
@@ -7,10 +35,21 @@
 setup(
     name='mensor',
     description="A dynamic graph-based metric computation engine.",
+    long_description=__doc__.strip(),
+    long_description_content_type='text/markdown',
     version=version_info['__version__'],
     author=version_info['__author__'],
     author_email=version_info['__author_email__'],
+    license='MIT',
+    url='http://github.com/airbnb/mensor',
+    project_urls={
+        'Documentation': 'http://mensor.readthedocs.io',
+        'Source': 'https://github.com/airbnb/mensor',
+        'Issue Tracker': 'https://github.com/airbnb/mensor/issues',
+    },
+    keywords='measures metrics aggregation experimentation statistics',
     packages=find_packages(),
+    python_requires='~=3.4',
     install_requires=version_info['__dependencies__'],
     classifiers=[
         'Development Status :: 3 - Alpha',
@@ -19,6 +58,7 @@
         'Intended Audience :: Information Technology',
         'Intended Audience :: Science/Research',
         'License :: OSI Approved :: MIT License',
+        'Programming Language :: Python :: 3',
         'Programming Language :: Python :: 3.4',
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',