Remove old node and npm versions from travis

Author: vweevers

.travis.yml

@@ -1,7 +1,5 @@
 language: node_js
 node_js:
-  - '0.10'
-  - '0.12'
-  - '4.0'
-before_install:
-  - npm install -g npm@~1.4.6
+  - 8
+  - 10
+  - 12