[openstack] Fix Authentication as well as Fog::JSON call bugs

Signed-off-by: Nelvin Driz <nelvindriz@live.com>

lib/fog/core/json.rb

@@ -43,4 +43,4 @@ module Fog
 
 
   end
-end
+end

lib/fog/openstack.rb

@@ -115,7 +115,7 @@ module Fog
             :method  => 'GET'
           })
 
-          body = MultiJson.decode(response.body)
+          body = Fog::JSON.decode(response.body)
           req_body['auth']['tenantName'] = body['tenants'].first['name']
         end
 
@@ -147,7 +147,7 @@ module Fog
       response = connection.request({
         :expects  => [200, 204],
         :headers  => {'Content-Type' => 'application/json'},
-        :body  => Fog::JSON.encode(req_body),
+        :body     => Fog::JSON.encode(request_body),
         :host     => uri.host,
         :method   => 'POST',
         :path     =>  (uri.path and not uri.path.empty?) ? uri.path : 'v2.0'

lib/fog/openstack/identity.rb

@@ -69,7 +69,6 @@ module Fog
         end
 
         def initialize(options={})
-          require 'multi_json'
           @openstack_username = options[:openstack_username]
 
           @data ||= { :users => {}}
@@ -107,8 +106,6 @@ module Fog
         attr_reader :current_tenant
 
         def initialize(options={})
-          require 'multi_json'
-
           @openstack_auth_token = options[:openstack_auth_token]
 
           unless @openstack_auth_token