[AppVeyor] push chocolatey package to the feeds

Makefile.win

@@ -61,3 +61,6 @@ package_choco:
 	cd out/choco && choco pack
 	mv out/choco/haxe.*.nupkg out
 	rm -rf out/choco
+	if [ -n "$$APPVEYOR" ]; then \
+	cd out/choco && appveyor PushArtifact haxe.*.nupkg; \
+	fi

appveyor.yml

@@ -72,4 +72,4 @@ test_script:
     - neko RunCi.n
 
 artifacts:
-    - path: out/*
+    - path: out/*.zip