Change README title from 'pylibcouchbase'

Change-Id: I8f1c4f5a52d7bb4dcd67a18134c0879b6413bb3e
Reviewed-on: http://review.couchbase.org/26441
Reviewed-by: Volker Mische <volker.mische@gmail.com>
Tested-by: Mordechai Nunberg <mnunberg@haskalah.org>