Made the nact dependecy looser

Author: ncthbrt

package.json

@@ -1,6 +1,6 @@
 {
   "name": "nact-persistence-postgres",
-  "version": "2.1.0",
+  "version": "2.1.1",
   "description": "PostgreSQL Persistence provider for NAct",
   "main": "lib/index.js",
   "scripts": {
@@ -28,7 +28,7 @@
     "url": "http://github.com/ncthbrt/nact-persistence-postgres/issues"
   },
   "dependencies": {
-    "nact": "^2.1.0",
+    "nact": "~2.1.0",
     "pg-reactive": "^0.3.2",
     "rxjs": "^5.4.3"
   },