Replace references to README.rst with README.md (#359)

* Replace references to README.rst with README.md

* Update desc content type

Author: cx1111

MANIFEST.in

@@ -2,11 +2,11 @@
 include LICENSE
 
 # Include readme file
-include README.rst
+include README.md
 
 # Include the data files
 # recursive-include data *
 
 # If using Python 2.6 or less, then have to include package data, even though
 # it's already declared in setup.py
-# include sample/*.dat
+# include sample/*.dat

setup.py

@@ -11,7 +11,7 @@
 here = path.abspath(path.dirname(__file__))
 
 # Get the long description from the README file
-with open(path.join(here, 'README.rst'), encoding='utf-8') as f:
+with open(path.join(here, 'README.md'), encoding='utf-8') as f:
     long_description = f.read()
 
 # Get the version number from the version.py file
@@ -28,6 +28,7 @@
 
     description='The WFDB Python Toolbox',
     long_description=long_description,
+    long_description_content_type="text/markdown",
 
     # The project's main homepage.
     url='https://github.com/MIT-LCP/wfdb-python',