Install qemu through choco and add it to the PATH

Author: phil-opp

.travis.yml

@@ -22,7 +22,7 @@ addons:
 
 install:
   - if [ $TRAVIS_OS_NAME = osx ]; then brew update; brew install qemu; fi
-  - if [ $TRAVIS_OS_NAME = windows ]; then wget https://qemu.weilnetz.de/w64/2018/qemu-w64-setup-20180801.exe; 7z x qemu-w64-setup-20180801.exe; fi
+  - if [ $TRAVIS_OS_NAME = windows ]; then choco install qemu; export PATH="/c/Program Files/qemu:$PATH"; fi
 
 before_script:
 - rustup component add rust-src