Add requirements.txt to MANIFEST. Also add version

checking for setuptools to setup.py.

MANIFEST.in

@@ -1 +1,2 @@
 include README.md
+include requirements.txt

README.md

@@ -1,8 +1,10 @@
 #capnpc-python-cpp
 
+More thorough docs are available at [http://jparyani.github.io/capnpc-python-cpp/](http://jparyani.github.io/capnpc-python-cpp/).
+
 ## Requirements
 
-First you need a system-wide installation of the Capnproto C++ library >= 0.3. Unfortunately, as of now, that means you have to build from the HEAD of Cap'n Proto. Follow these instructions to do so:
+First you need a system-wide installation of the Cap'n Proto C++ library >= 0.3. Unfortunately, as of now, that means you have to build from the HEAD of Cap'n Proto. Follow these instructions to do so:
 
 ```bash
 wget https://github.com/kentonv/capnproto/archive/master.zip

setup.py

@@ -6,7 +6,12 @@ except ImportError:
     raise RuntimeError('No cython installed. Please run `pip install cython`')
 
 if Cython.__version__ < '0.19.1':
-    raise RuntimeError('Old cython installed. Please run `pip install -U cython`')
+    raise RuntimeError('Old cython installed (%s). Please run `pip install -U cython`' % Cython.__version__)
+
+import pkg_resources
+setuptools_version = pkg_resources.get_distribution("setuptools").version
+if setuptools_version < '0.8':
+    raise RuntimeError('Old setuptools installed (%s). Please run `pip install -U setuptools`. Running `pip install capnp` will not work alone, since setuptools needs to be upgraded before installing anything else.' % setuptools_version)
 
 from distutils.core import setup
 import os
@@ -16,7 +21,6 @@ MINOR = 3
 MICRO = 5
 VERSION = '%d.%d.%d' % (MAJOR, MINOR, MICRO)
 
-
 def write_version_py(filename=None):
     cnt = """\
 version = '%s'