v6.0.0: drop node <16 support

Author: zaggino

Diff for: .github/workflows/node.js.yml

@@ -16,7 +16,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [14.x, 16.x, 18.x]
+        node-version: [18.x, 16.x]
         # See supported Node.js release schedule at https://nodejs.org/en/about/releases/
 
     steps:

Diff for: .travis.yml

@@ -1,9 +1,7 @@
 language: node_js
 node_js:
-  - "14"
-  - "12"
-  - "10"
-  - "8"
+  - "18"
+  - "16"
 sudo: false
 before_install:
   - npm install -g grunt-cli