Ensure supporting files are included in source distribution

These supporting files should be included in the source
distribution shipped to PyPI. Most critically, the LICENSE
ought to be shipped with the source.

Also removes the code in setup.py tolerating absence of README.md.
The reason it was missing for older python/setuptools was that
README.md isn't implicitly included in the source dist for those
old versions.

Author: rohanpm

Diff for: CHANGELOG.md

@@ -7,7 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## Unreleased
 
-- n/a
+### Fixed
+
+- Added missing files (changelog, license) to PyPI distribution
 
 ## 1.0.0 - 2019-02-07
 

Diff for: MANIFEST.in

@@ -0,0 +1,3 @@
+include README.md
+include CHANGELOG.md
+include LICENSE

Diff for: setup.py

@@ -6,13 +6,8 @@ def get_description():
 
 
 def get_long_description():
-    try:
-        text = open('README.md').read()
-    except IOError as error:
-        if error.errno == 2:
-            # fallback for older setuptools
-            return get_description()
-        raise
+    with open('README.md') as f:
+        text = f.read()
 
     # Long description is everything after README's initial heading
     idx = text.find('\n\n')