Fast finish for ci

appveyor.yml

@@ -2,6 +2,10 @@
 environment:
   nodejs_version: "8"
 
+# this is how to allow failing jobs in the matrix
+matrix:
+  fast_finish: true     # set this flag to immediately finish build once one of the jobs fails.
+
 # Install scripts. (runs after repo cloning)
 install:
   # Get the latest stable version of Node.js or io.js