ci: add node 16

Author: wallet77

.github/workflows/node.js.yml

@@ -15,7 +15,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [12.x, 14.x]
+        node-version: [12.x, 14.x, 16]
 
     steps:
     - uses: actions/checkout@v2

README.md

@@ -28,6 +28,7 @@ Supported and tested : >= 7.6
 
 | Version       | Supported     | Tested         |
 | ------------- |:-------------:|:--------------:|
+| 16.x          | yes           | yes            |
 | 14.x          | yes           | yes            |
 | 12.x          | yes           | yes            |
 | 10.x          | yes           | yes            |