Updated and extended README.
Updated and extended README.

kevinyien/couchdb-client,dungphanxuan/couchdb-client,timmillwood/couchdb-client,relaxedws/couchdb-client,doctrine/couchdb-client,dungphanxuan/couchdb-client,timmillwood/couchdb-client,doctrine/couchdb-client,kevinyien/couchdb-client,relaxedws/couchdb-client