I want be able to get token via api. Used for mobile applications

doc/api/session.md

@@ -0,0 +1,22 @@
+Login to get private token
+
+```
+POST /session
+```
+
+Parameters:
+
++ `email` (required) - The email of user
++ `password` (required) - Valid password
+
+
+```json
+{
+  "id": 1,
+  "email": "john@example.com",
+  "name": "John Smith",
+  "private_token": "dd34asd13as",
+  "created_at": "2012-05-23T08:00:58Z",
+  "blocked": true
+}
+```