update

SUMMARY.md

@@ -1 +1,4 @@
 # Summary
+
+* [Introduction](README.md)
+

book.json

@@ -1,5 +1,5 @@
 {
-  "gitbook": "3.0.0-pre.9",
+  "gitbook": ">=3.x.x",
   "title": "Krestianstvo SDK projects",
   "description": "Book on Krestianstvo SDK projects",
   "plugins": ["ga"],