Added dependencies

requirements.txt

+requests==1.2.3
+requests_oauth==0.4.1

setup.py

@@ -2,6 +2,10 @@
 #from distutils.core import setup
 from setuptools import setup, find_packages
 from tweepy import __version__
+from pip.req import parse_requirements
+
+install_reqs = parse_requirements('requirements.txt')
+reqs = [str(req.req) for req in install_reqs]
 
 setup(name="tweepy",
       version=__version__,
@@ -11,5 +15,6 @@ setup(name="tweepy",
       author_email="tweepy@googlegroups.com",
       url="http://github.com/tweepy/tweepy",
       packages=find_packages(exclude=['tests']),
+      intall_requires=reqs,
       keywords="twitter library",
       zip_safe=True)