Add installation instructions to readme

Also, fix broken badge link.

Author: hickford

README.rst

@@ -6,6 +6,20 @@ aims at allowing full access to loose objects as well as packs with performance
 and scalability in mind. It operates exclusively on streams, allowing to operate 
 on large objects with a small memory footprint.
 
+Installation
+============
+
+.. image:: https://pypip.in/version/gitdb/badge.svg
+    :target: https://pypi.python.org/pypi/gitdb/
+    :alt: Latest Version
+.. image:: https://pypip.in/py_versions/gitdb/badge.svg
+    :target: https://pypi.python.org/pypi/gitdb/
+    :alt: Supported Python versions
+
+From `PyPI <https://pypi.python.org/pypi/gitdb>`_
+
+ pip install gitdb
+
 REQUIREMENTS
 ============
 
@@ -33,8 +47,9 @@ http://groups.google.com/group/git-python
 ISSUE TRACKER
 =============
 
-.. image:: https://travis-ci.org/gitpython-developers/gitdb.svg?branch=master   :target: https://travis-ci.org/gitpython-developers/gitdb
-
+.. image:: https://travis-ci.org/gitpython-developers/gitdb.svg?branch=master
+    :target: https://travis-ci.org/gitpython-developers/gitdb
+    
 https://github.com/gitpython-developers/gitdb/issues
 
 LICENSE