Fixed up mistakes in the readme example code

Author: iainbeeston

README.md

@@ -1,8 +1,8 @@
 # JsonValidator
 
+[![Gem Version](http://img.shields.io/gem/v/json_validator.svg)](https://rubygems.org/gems/json_validator)
 [![Build Status](http://img.shields.io/travis/iainbeeston/json_validator/master.svg)](https://travis-ci.org/iainbeeston/json_validator)
 [![Code Climate](http://img.shields.io/codeclimate/github/iainbeeston/json_validator.svg)](https://codeclimate.com/github/iainbeeston/json_validator)
-[![Gem Version](http://img.shields.io/gem/v/json_validator.svg)](https://rubygems.org/gems/json_validator)
 
 
 JsonValidator is an ActiveModel validator that validates any hash field against [JSONSchema](http://json-schema.org), returning errors in the model's own `errors` attribute.
@@ -18,7 +18,7 @@ If you're using Ruby on Rails and ActiveRecord, add a validation to your model l
 ~~~ruby
 class Foo < ActiveRecord::Base
   validates :bar, json: {
-    schema: File.read(JSON.parse('foo_schema.json'))
+    schema: JSON.parse(File.read('foo_schema.json'))
   }
 end
 ~~~
@@ -27,7 +27,7 @@ And you have a schema file (ie. `foo_schema.json`) like this:
 
 ~~~json
 {
-  "$schema": "http://json-schema.org/schema#",
+  "$schema": "http://json-schema.org/draft-04/schema#",
   "title": "Universal spoons schema",
     "properties": {
       "handleSize": {
@@ -39,6 +39,14 @@ And you have a schema file (ie. `foo_schema.json`) like this:
 }
 ~~~
 
-Then whenever an instance of `Foo` is saved, `Foo.bar` (assumed to be a hash) will be validated against the JSON schema specified. In this case, `Foo.new(bar: { handleSize: -10 })` would be invalid, but `Foo.new(bar: { handleSize: 10 })` would be valid.
+Then whenever an instance of `Foo` is saved, `Foo.bar` (assumed to be a hash) will be validated against the JSON schema specified. So, for example:
+
+~~~ruby
+
+f = Foo.new(bar: { handleSize: -10 })
+f.valid? # false
+f.errors.full_messages # ["Bar is invalid (the property '#/handleSize' did not have a minimum value of 0, inclusively)"]
+
+~~~
 
 The attribute being validated can be either a hash or a string (which will be parsed as JSON). The schema can be either a hash or a Proc that returns a hash (if you'd like to decide on the schema at runtime), and there's no reason why you could not load your schema from a .json file.