chore: remove very old nodejs

Author: deleonio

.travis.yml

@@ -10,10 +10,10 @@ cache:
     - node_modules
 
 node_js:
-   - 0.10 # to be removed 2016-10-01
-   - 0.12 # to be removed 2016-12-31
-   - 4 # to be removed 2018-04-01
-   - 6 # to be removed 2019-04-01
+  #  - 0.10 # to be removed 2016-10-01
+  #  - 0.12 # to be removed 2016-12-31
+  #  - 4 # to be removed 2018-04-01
+  #  - 6 # to be removed 2019-04-01
    - lts/* # safety net; don't remove
    - node # safety net; don't remove