Return 201 status from POST collection endpoint

-Resolve task in Issue #48
  - 201 is the standard HTTP response code when a resource is created,
    which is done in a POST collection endpoint.
- Update README to include info about successful response codes (just a
  band-aid fix until the apiDoc is ready)

README.md

@@ -475,8 +475,8 @@ object containing the following properties:
 ### Request and Response Structure
 
 All responses generated by Restivus follow the [JSend] format, with one minor tweak: failures have
-an identical structure to errors. Sample requests and responses for each endpoint are included
-below:
+an identical structure to errors. Successful responses will have a status code of `200`, unless 
+otherwise indicated. Sample requests and responses for each endpoint are included below:
 
 #### `post`
 Request:
@@ -485,6 +485,8 @@ curl -X POST http://localhost:3000/api/posts/ -d "title=Witty Title" -d "author=
 ```
 
 Response:
+
+Status Code: `201`
 ```json
 {
   "status": "success",
@@ -623,6 +625,8 @@ name in the [Accounts.createUser()](http://docs.meteor.com/#/full/accounts_creat
 check that out for more information on how those fields are handled._
 
 Response:
+
+Status Code: `201`
 ```json
 {
   "status": "success",

lib/restivus.coffee

@@ -168,10 +168,11 @@ class @Restivus
           entityId = collection.insert @bodyParams
           entity = collection.findOne entityId
           if entity
-            {status: "success", data: entity}
+            statusCode: 201
+            body: {status: "success", data: entity}
           else
             statusCode: 400
-            {status: "fail", message: "No item added"}
+            body: {status: "fail", message: "No item added"}
     getAll: (collection) ->
       get:
         action: ->
@@ -230,7 +231,8 @@ class @Restivus
           entityId = Accounts.createUser @bodyParams
           entity = collection.findOne entityId, fields: profile: 1
           if entity
-            {status: "success", data: entity}
+            statusCode: 201
+            body: {status: "success", data: entity}
           else
             statusCode: 400
             {status: "fail", message: "No user added"}