restore old node versions in travis

mcollina · mcollina · commit 810a95c94b8c · 2020-04-29T12:45:07.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -4,6 +4,8 @@ node_js:
   - "14"
   - "12"
   - "10"
+  - "8"
+  - "6"
 
 services:
   - redis-server
