ENH: Added Python library for CouchDB connection
CouchDB is a NoSQL database that provides document-based data storage (http://couchdb.apache.org/). It complements Slicer's file-based and SQLite-based data storage solutions.
Couchdb-python is a small native Python client library that makes database access very convenient: https://github.com/djc/couchdb-python
This commits adds this small Python package to the Slicer installation package, similarly to python-async python-chardet python-gitdb python-GitPython python-nose python-pydicom python-PyGithub python-smmap.