Make sure properties get overridden successfully

[pksunkara]

Using the current boutique.js, when we are expanding MSON of the following blueprint, the properties of an object, doesn't get overridden correctly and contains duplicates.

FORMAT: 1A
HOST: http://parametrizedmson.apiblueprint.org/

# Testing parametrized MSON

Just testing parametrized MSON.

# Resource A [/a]
## Create [GET]
+ request (application/json)
  + attributes (A)

+ response 201

+ request (application/json)
  + attributes (A)
      + a2: 42

+ response 400



# Data Structures
## A (object)
+ a1: 1
+ a2: 2

The rendered JSON should be

{
  "a1": "1",
  "a2": "42"
}

And the MSON table should be the following

Name	Type	Required	Description	Value
a1	optional	1
a2	optional	2

The MSON table is currently the following

Name	Type	Required	Description	Value
a2	optional	42
a1	optional	1
a2	optional	2

[pksunkara]

Related to apiaryio/mson#28

[pksunkara]

The rendered JSON is fixed now in master branch.

[pksunkara]

The actual display of attributes will be tackled in the now infamous apiaryio/api-blueprint#191