add download count

README.md

@@ -6,6 +6,10 @@ Greenlock™ for node.js
 Greenlock provides Free SSL, Free Wildcard SSL, and Fully Automated HTTPS <br>
 <small>certificates issued by Let's Encrypt v2 via [ACME](https://git.coolaj86.com/coolaj86/acme-v2.js)</small>
 
+!["Lifetime Downloads"](https://img.shields.io/npm/dt/greenlock.svg "Lifetime Download Count can't be shown")
+!["Monthly Downloads"](https://img.shields.io/npm/dm/greenlock.svg "Monthly Download Count can't be shown")
+!["Weekly Downloads"](https://img.shields.io/npm/dw/greenlock.svg "Weekly Download Count can't be shown")
+
 | Sponsored by [ppl](https://ppl.family) |
 Greenlock works
 in the [Commandline](https://git.coolaj86.com/coolaj86/greenlock-cli.js) (cli),