Fix MANIFEST.in and remove workaround from setup.py

MANIFEST.in

 include *.txt
+include *.rst
 
 recursive-include docs *
 recursive-include persistent *
@@ -7,3 +8,9 @@ global-exclude *.dll
 global-exclude *.pyc
 global-exclude *.pyo
 global-exclude *.so
+
+include .coveragerc
+include .travis.yml
+include buildout.cfg
+include tox.ini
+include *.py

setup.py

@@ -25,12 +25,11 @@ from setuptools import setup
 
 here = os.path.abspath(os.path.dirname(__file__))
 
+
 def _read_file(filename):
-    try:
     with open(os.path.join(here, filename)) as f:
         return f.read()
-    except IOError:  # Travis???
-        return ''
+
 
 README = (_read_file('README.rst') + '\n\n' + _read_file('CHANGES.rst'))