Fix win executable file name

Author: mjackson

.travis.yml

@@ -23,7 +23,7 @@ deploy:
 - provider: releases
   api_key: "$GITHUB_TOKEN"
   file:
-    - "build/$TRAVIS_TAG/win-x64/react-stdio"
+    - "build/$TRAVIS_TAG/win-x64/react-stdio.exe"
     - "build/$TRAVIS_TAG/linux-x64/react-stdio"
     - "build/$TRAVIS_TAG/macos/react-stdio"
   skip_cleanup: true