Update .travis.yml

Rollback to node 8

Author: danielo515

.travis.yml

@@ -3,7 +3,7 @@ cache:
   directories:
     - ~/.npm
 node_js:
-  - "12"
+  - "8"
 before_install:
   - "npm i -g tiddlywiki@5.1.21"
   - "git clone https://github.com/danielo515/tw5-pouchdb.git pouchdb" # note that I'm naming the output folders for easier reference later