Re-added OpenCV env vars for windows builds

Author: Simon Hofmann

appveyor.yml

@@ -31,10 +31,10 @@ environment:
 
 install:
   # - cmd: choco install OpenCV -y -version %OPENCV_VERSION%
-  # - if not "%BUILD_TASK%" == "ENVS" SET OPENCV_INCLUDE_DIR=c:\tools\opencv\build\include
-  # - if not "%BUILD_TASK%" == "ENVS" SET OPENCV_LIB_DIR=c:\tools\opencv\build\x64\vc14\lib
-  # - if not "%BUILD_TASK%" == "ENVS" SET OPENCV_BIN_DIR=c:\tools\opencv\build\x64\vc14\bin
-  # - if not "%BUILD_TASK%" == "ENVS" SET PATH=%PATH%;%OPENCV_BIN_DIR%;
+  - if not "%BUILD_TASK%" == "ENVS" SET OPENCV_INCLUDE_DIR=c:\tools\opencv\build\include
+  - if not "%BUILD_TASK%" == "ENVS" SET OPENCV_LIB_DIR=c:\tools\opencv\build\x64\vc14\lib
+  - if not "%BUILD_TASK%" == "ENVS" SET OPENCV_BIN_DIR=c:\tools\opencv\build\x64\vc14\bin
+  - if not "%BUILD_TASK%" == "ENVS" SET PATH=%PATH%;%OPENCV_BIN_DIR%;
   - ps: Install-Product node $env:nodejs_version x64
   - node --version