如图所示，之前四个示例都通过了，但是跑到第五个 webview 的示例就出错了，提示找不到 ios simulator，求帮助。
iOS simulator 一直都是正常运行的，直到以下这个地方就停止报错 了：
ios_webkit_debug_proxy path: /usr/local/bin/ios_webkit_debug_proxy
Error: Device: SIMULATOR does not exist.
at request.get.then.then.devices (/usr/local/lib/node_modules/macaca-ios/node_modules/remote-debugger/lib/remote-debugger.js:47:17)
at tryCatcher (/usr/local/lib/node_modules/macaca-ios/node_modules/bluebird/js/main/util.js:26:23)
at Promise._settlePromiseFromHandler (/usr/local/lib/node_modules/macaca-ios/node_modules/bluebird/js/main/promise.js:510:31)
at Promise._settlePromiseAt (/usr/local/lib/node_modules/macaca-ios/node_modules/bluebird/js/main/promise.js:584:18)
at Promise._settlePromises (/usr/local/lib/node_modules/macaca-ios/node_modules/bluebird/js/main/promise.js:700:14)
at Async._drainQueue (/usr/local/lib/node_modules/macaca-ios/node_modules/bluebird/js/main/async.js:123:16)
at Async._drainQueues (/usr/local/lib/node_modules/macaca-ios/node_modules/bluebird/js/main/async.js:133:10)
at Immediate.Async.drainQueues (/usr/local/lib/node_modules/macaca-ios/node_modules/bluebird/js/main/async.js:15:14)
at runCallback (timers.js:566:20)
at tryOnImmediate (timers.js:546:5)
at processImmediate as _immediateCallback
1) #5 should go into webview
RequestError: Error: connect ECONNREFUSED 127.0.0.1:80
at new RequestError (/usr/local/lib/node_modules/macaca-ios/node_modules/request-promise/lib/errors.js:11:15)
at Request.RP$callback as _callback
at self.callback (/usr/local/lib/node_modules/macaca-ios/node_modules/request/request.js:186:22)
at emitOne (events.js:96:13)
at Request.emit (events.js:188:7)
at Request.onRequestError (/usr/local/lib/node_modules/macaca-ios/node_modules/request/request.js:845:8)
at emitOne (events.js:96:13)
at ClientRequest.emit (events.js:188:7)
at Socket.socketErrorListener (_http_client.js:308:9)
at emitOne (events.js:96:13)
at Socket.emit (events.js:188:7)
at emitErrorNT (net.js:1272:8)
at _combinedTickCallback (internal/process/next_tick.js:74:11)
at process._tickCallback (internal/process/next_tick.js:98:9)
2) #6 should go into test
RequestError: Error: connect ECONNREFUSED 127.0.0.1:80
at new RequestError (/usr/local/lib/node_modules/macaca-ios/node_modules/request-promise/lib/errors.js:11:15)
at Request.RP$callback as _callback
at self.callback (/usr/local/lib/node_modules/macaca-ios/node_modules/request/request.js:186:22)
at emitOne (events.js:96:13)
at Request.emit (events.js:188:7)
at Request.onRequestError (/usr/local/lib/node_modules/macaca-ios/node_modules/request/request.js:845:8)
at emitOne (events.js:96:13)
at ClientRequest.emit (events.js:188:7)
at Socket.socketErrorListener (_http_client.js:308:9)
at emitOne (events.js:96:13)
at Socket.emit (events.js:188:7)
at emitErrorNT (net.js:1272:8)
at _combinedTickCallback (internal/process/next_tick.js:74:11)
at process._tickCallback (internal/process/next_tick.js:98:9)
3) #7 should works with web
RequestError: Error: connect ECONNREFUSED 127.0.0.1:80
at new RequestError (/usr/local/lib/node_modules/macaca-ios/node_modules/request-promise/lib/errors.js:11:15)
at Request.RP$callback as _callback
at self.callback (/usr/local/lib/node_modules/macaca-ios/node_modules/request/request.js:186:22)
at emitOne (events.js:96:13)
at Request.emit (events.js:188:7)
at Request.onRequestError (/usr/local/lib/node_modules/macaca-ios/node_modules/request/request.js:845:8)
at emitOne (events.js:96:13)
at ClientRequest.emit (events.js:188:7)
at Socket.socketErrorListener (_http_client.js:308:9)
at emitOne (events.js:96:13)
at Socket.emit (events.js:188:7)
at emitErrorNT (net.js:1272:8)
at _combinedTickCallback (internal/process/next_tick.js:74:11)
at process._tickCallback (internal/process/next_tick.js:98:9)
4) #8 should logout success
Listing devices on :9221
ios_webkit_debug_proxy exit with code: 0, signal: null
4 passing (2m)
4 failing