Remove unused CloudantError

Author: smithsz

lib/client.js

@@ -15,7 +15,6 @@
 
 const async = require('async');
 const concat = require('concat-stream');
-const CloudantError = require('./error.js');
 const debug = require('debug')('cloudant:client');
 const EventRelay = require('./eventrelay.js');
 const PassThroughDuplex = require('./passthroughduplex.js');