Added Greenkeeper.io icon (#1458)

Closes #1457

_data/simple-icons.json

@@ -1120,6 +1120,11 @@
             "hex": "1E8CBE",
             "source": "https://automattic.com/press"
         },
+        {
+            "title": "Greenkeeper",
+            "hex": "00C775",
+            "source": "https://greenkeeper.io/"
+        },
         {
             "title": "Groupon",
             "hex": "53A318",

icons/greenkeeper.svg

@@ -0,0 +1 @@
+<svg role="img" viewBox="0 0 24 24" xmlns="http://www.w3.org/2000/svg"><title>Greenkeeper icon</title><path d="M12.04 22.547a2.206 2.206 0 0 1-2.014-3.108l-2.699-1.8a2.201 2.201 0 1 1 .42-.626l2.702 1.8c.082-.085.172-.164.267-.236l-4.33-8.659a2.209 2.209 0 1 1 .672-.343l4.33 8.659c.077-.024.156-.044.235-.059v-4.128a2.206 2.206 0 0 1 0-4.333v-3.89a2.206 2.206 0 1 1 .755.014v3.866a2.205 2.205 0 0 1 0 4.359v4.097c.082.013.164.03.244.052l4.32-8.638a2.202 2.202 0 1 1 .672.344l-4.309 8.617c.1.07.194.148.28.233l2.616-1.776a2.209 2.209 0 1 1 .44.613l-2.615 1.777a2.206 2.206 0 0 1-1.986 3.165zM12 24C5.373 24 0 18.628 0 12a12 12 0 0 1 3.515-8.485c4.686-4.686 12.284-4.686 16.97 0s4.687 12.284 0 16.97A11.921 11.921 0 0 1 12 24zM12 .755C5.79.755.755 5.79.755 12c0 2.982 1.185 5.843 3.294 7.951 4.376 4.407 11.495 4.433 15.902.057s4.432-11.496.057-15.903A11.173 11.173 0 0 0 12 .755z"/></svg>