Update README and setup.py to reflect Python 3 compatibility

Author: vgel

README.md

@@ -3,28 +3,32 @@ summarize.py
 
 A python script for summarizing articles using nltk.
 
-Requires:
+## Requires:
+* python2.7 / python 3
+* nltk (if using Python 3, see note below)
+* bs4 (only for opening urls)
+* requests (only for opening urls)
 
-    python2.7
-    nltk
-    bs4 (only for opening urls)
-    requests (only for opening urls)
-  
-Usage:
+## Usage:
 
     git clone https://github.com/Rotten194/summarize.py.git
     cd summarize.py
     ./summarize.py http://www.washingtonpost.com/blogs/the-switch/wp/2013/08/01/how-vermont-could-save-the-nation-from-patent-trolls/
 
-Example:
+## Python 3 Support Notes:
+
+To use NLTK with Python 3 currently, you must install the NLTK 3.0 alpha packages available at [nltk.org](http://www.nltk.org/nltk3-alpha). All other libraries required by summarize.py have Python 3 versions.
+
+
+## Example:
 
     $ ./summarize.py http://www.theverge.com/2013/8/1/4580718/fbi-can-remotely-activate-android-and-laptop-microphones-reports-wsj
     FBI can remotely activate Android and laptop microphones, reports WSJ | The Verge
-    
+
     The Wall Street Journal reports that the FBI can already remotely activate those microphones to record conversations.
-    
+
     Remotely activated cell phone bugs predate iOS and Android
-    
+
     What's new, according to several former anonymous officials, is a dedicated FBI group which regularly hacks into computers, using both custom and off-the-shelf surveillance software which it buys from private companies.
-    
+
     " While that source also claims the FBI takes care to make sure that only "relevant data" gets collected, it's still a little troubling to know that such a thing is easily possible and regularly done.

setup.py

@@ -36,7 +36,9 @@
         'Natural Language :: English',
         'License :: OSI Approved :: BSD License',
         'Programming Language :: Python',
-        "Programming Language :: Python :: 2",
+        'Programming Language :: Python :: 2',
         'Programming Language :: Python :: 2.7',
+        'Programming Language :: Python :: 3',
+        'Programming Language :: Python :: 3.3'
     ],
 )