lib/client.js
function(publicKey, callback) {
        request.head(
            this.getResourceUrl({ path: '/keys/' + publicKey, user: null }),
            get404Handler(callback)
        );
        return this;
    }
function(publicKey, callback) {
        request.head(
            this.getResourceUrl({ path: '/keys/' + publicKey, user: null }),
            get404Handler(callback)
        );
        return this;
    }
function ( publicKey , callback ) { request . head ( this . getResourceUrl ( { path : '/keys/' + publicKey , user : null } ) , get404Handler ( callback ) ) ; return this ; }
Check whether a public key exists or not

@param {String} publicKey Public key you want to check for the presence of
@param {Function} callback
@return {ImboClient}
Check whether a public key exists or not