Added node 8 to the tests as it is the latest version

.appveyor.yml

@@ -3,8 +3,8 @@ environment:
   matrix:
     - nodejs_version: "6"
     # - nodejs_version: "7"
-    # - nodejs_version: "8" 
-    - nodejs_version: "9"
+    - nodejs_version: "8" 
+    # - nodejs_version: "10"
 platform:
   # - x86
   - x64

.travis.yml

@@ -2,6 +2,7 @@ sudo: false
 language: node_js
 node_js:
 - '6'
+- '8'
 notifications:
   email: false
   slack: