v3.1.0: add CLI and more reasonable defaults

package-lock.json

@@ -1,6 +1,6 @@
 {
     "name": "@root/greenlock",
-    "version": "3.1.0-wip",
+    "version": "3.1.0",
     "lockfileVersion": 1,
     "requires": true,
     "dependencies": {

package.json

@@ -1,6 +1,6 @@
 {
     "name": "@root/greenlock",
-    "version": "3.1.0-wip",
+    "version": "3.1.0",
     "description": "The easiest Let's Encrypt client for Node.js and Browsers",
     "homepage": "https://rootprojects.org/greenlock/",
     "main": "greenlock.js",