chore: drop node 6 and 8 support (#90)

diff --git a/.travis.yml b/.travis.yml
index 2361f5d..af50820 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -5,8 +5,6 @@
   depth: 10
 
 node_js:
-  - 6
-  - 8
   - 10
   - 12
 
diff --git a/appveyor.yml b/appveyor.yml
index 5267502..d48ddc8 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -5,8 +5,6 @@
 
 environment:
   matrix:
-  - nodejs_version: 6
-  - nodejs_version: 8
   - nodejs_version: 10
   - nodejs_version: 12
 
diff --git a/package.json b/package.json
index 783acfc..b1e0d1f 100644
--- a/package.json
+++ b/package.json
@@ -14,7 +14,7 @@
   },
   "main": "cordova-common.js",
   "engines": {
-    "node": ">=6.0.0"
+    "node": ">=10.0.0"
   },
   "scripts": {
     "test": "npm run eslint && npm run jasmine",