add node 10, remove node 0.12, 5 and 7

Author: Lars-Magnus Skog

.travis.yml

@@ -1,28 +1,8 @@
 language: node_js
+
 node_js:
-  - "8"
-  - "7"
-  - "6"
-  - "5"
-  - "4"
-  - "0.12"
-branches:
-  only:
-    - master
-    - /^greenkeeper/.*$/
-notifications:
-  email:
-    - r@va.gg
-    - john@chesl.es
-    - raynos2@gmail.com
-    - dominic.tarr@gmail.com
-    - max@maxogden.com
-    - ralphtheninja@riseup.net
-    - david.bjorklund@gmail.com
-    - julian@juliangruber.com
-    - paolo@async.ly
-    - anton.whalley@nearform.com
-    - matteo.collina@gmail.com
-    - pedro.teixeira@gmail.com
-    - mail@substack.net
-script: npm test
+  - 10
+  - 9
+  - 8
+  - 6
+  - 4