update appveyor

AtsushiSakai · AtsushiSakai · commit ce77d7691c75 · 2018-10-21T21:14:52.000+09:00
diff --git a/appveyor.yml b/appveyor.yml
@@ -7,6 +7,7 @@ init:
   - "ECHO %PYTHON% %PYTHON_VERSION% %PYTHON_ARCH%"
 
 install:
+  - "%PYTHON%\\python.exe -m pip install wheel"
   - "%PYTHON%/Scripts/pip.exe install numpy"
   - "%PYTHON%/Scripts/pip.exe install pandas"
   - "%PYTHON%/Scripts/pip.exe install scipy"
