switch to official couchbase-lite-core

Author: Dushistov

.gitmodules

@@ -1,3 +1,3 @@
 [submodule "couchbase-lite-core-sys/couchbase-lite-core"]
 	path = couchbase-lite-core-sys/couchbase-lite-core
-	url = https://github.com/Dushistov/couchbase-lite-core
+	url = https://github.com/couchbase/couchbase-lite-core