Added a seperate requirements file for PIP and updated setup.py to use with while reading README and CHANGES

requirements.txt

@@ -0,0 +1,5 @@
+pyramid
+waitress
+transaction
+zope.sqlalchemy
+SQLAlchemy

setup.py

@@ -3,8 +3,10 @@ import os
 from setuptools import setup, find_packages
 
 here = os.path.abspath(os.path.dirname(__file__))
-README = open(os.path.join(here, 'README.txt')).read()
-CHANGES = open(os.path.join(here, 'CHANGES.txt')).read()
+with open(os.path.join(here, 'README.txt')) as f:
+    README = f.read()
+with open(os.path.join(here, 'CHANGES.txt')) as f:
+    CHANGES = f.read()
 
 requires = [
     'pyramid',