partly revert a80534f2: do not auto-recreate README (rst) during install

to avoid auto-version determining scheme finding dirty repo state

setup.py

@@ -15,9 +15,6 @@ from setuptools import setup
 try:
     from pypandoc import convert_file
     read_md = lambda f: convert_file(f, 'rst', format='md')
-    # auto-create RST version of README
-    with open('README', 'w') as f:
-        f.write(read_md('README.md'))
 except ImportError:
     print("warning: pypandoc module not found, could not convert Markdown to RST")
     read_md = lambda f: open(f, 'r').read()