Safely update npm on Travis (#42)

lukechilds · web-flow · commit 986fc8d78fcb · 2019-04-11T16:33:59.000+07:00
This resolves most of the failing tests on Travis.
diff --git a/.travis.yml b/.travis.yml
@@ -1,7 +1,6 @@
 language: node_js
 before_install:
-  - npm install -g npm@2
-  - npm install -g npm
+  - nvm install-latest-npm
 matrix:
   include:
   - node_js: '0.8'
