Fix gateway kernelspec tests to updated JKM call

Author: kevin-bates

appveyor.yml

@@ -23,4 +23,6 @@ install:
   - cmd: pip install git+https://github.com/gateway-experiments/jupyter_kernel_mgmt.git@fix-windows
 
 test_script:
-  - nosetests  -v jupyter_server --exclude-dir notebook\tests\selenium
+  - nosetests -v jupyter_server.services.kernels.tests
+  - nosetests -v jupyter_server.tests.test_utils
+  #- nosetests  -v jupyter_server --exclude-dir notebook\tests\selenium

jupyter_server/gateway/managers.py

@@ -1,13 +1,14 @@
 # Copyright (c) Jupyter Development Team.
 # Distributed under the terms of the Modified BSD License.
-
+import asyncio
 import os
 import json
 import logging
 
 from jupyter_kernel_mgmt.discovery import KernelFinder
 from socket import gaierror
 from tornado import gen, web
+from tornado.concurrent import Future
 from tornado.escape import json_encode, json_decode, url_escape
 from tornado.httpclient import HTTPClient, AsyncHTTPClient, HTTPError
 
@@ -519,15 +520,13 @@ def _get_kernelspecs_endpoint_url(self, kernel_name=None):
 
         return self.base_endpoint
 
-    @gen.coroutine
+    @asyncio.coroutine
     def find_kernels(self):
-        remote_kspecs_list = []
-        remote_kspecs = yield maybe_future(self.get_all_specs())
+        remote_kspecs = yield from self.get_all_specs()
+
         # convert to list of 2 tuples
         for kernel_type, attributes in remote_kspecs.items():
-            remote_kspecs_list.append((kernel_type, attributes))
-
-        raise gen.Return(remote_kspecs_list)
+            yield kernel_type, attributes
 
     @gen.coroutine
     def get_all_specs(self):