Merge pull request #1196 from Gwill/dev

修改 Travis 在 py3.6 环境下无法通过的问题

.gitignore

@@ -58,6 +58,7 @@ build/Makefile
 .python-version
 .gitignore
 temp/
+.venv
 
 # setup.py install 临时文件
 dist

tests/Promise.py

@@ -30,7 +30,7 @@ class Promise(object):
             raise res[1]
         else:
             et, ev, tb = res[1]
-            raise et, ev, tb
+            raise et(ev).with_traceback(tb)
     
     def set_exception(self, valueOrType, val=None, tb=None):
         if val is None:

vnpy/trader/vtEngine.py

@@ -413,7 +413,7 @@ class DataEngine(object):
         self.workingOrderDict = {}  # 可撤销委托
         self.tradeDict = {}
         self.accountDict = {}
-        self.positionDict= {}
+        self.positionDict = {}
         self.logList = []
         self.errorList = []