build: fix jshint unused variable warnings

lib/bus.js

@@ -2,8 +2,6 @@
 
 var events = require('events');
 var util = require('util');
-var bitcore = require('bitcore-lib');
-var _ = bitcore.deps._;
 
 /**
  * The bus represents a connection to node, decoupled from the transport layer, that can

lib/services/bitcoind.js

@@ -5,7 +5,6 @@ var spawn = require('child_process').spawn;
 var util = require('util');
 var mkdirp = require('mkdirp');
 var bitcore = require('bitcore-lib');
-var Address = bitcore.Address;
 var zmq = require('zmq');
 var async = require('async');
 var LRU = require('lru-cache');