Add GCS config examples

Author: ddattee

doc/config/sync/googlecloudstorage.json

@@ -0,0 +1,8 @@
+{
+  "type": "googlecloudstorage",
+  "options": {
+    "secret": "backup/google/client_secret.json",
+    "bucket": "my-bucket",
+    "path": "remote/path"
+  }
+}

doc/config/sync/googlecloudstorage.xml

@@ -0,0 +1,15 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<sync type="googlecloudstorage">
+  <!-- google secret file -->
+  <option name="secret" value="backup/google/client_secret.json"/>
+
+  <!-- bucket name to upload to -->
+  <option name="bucket" value="backup/google/client_secret.json"/>
+
+  <!-- the remote path to upload to int the bucket -->
+  <option name="path" value="remote/path"/>
+
+  <!-- optional cleanup configuration -->
+  <option name="cleanup.type" value="quantity"/>
+  <option name="cleanup.amount" value="10"/>
+</sync>