moved subject settor for realm_id into the test itself to close deprecation warnings from RSpec
Squashed commit of the following:

commit 7901293f28eebf9e2b25c124a56ea475c6a40c21
Merge: efb84b4 859811c
Author: Cody Caughlan <toolbag@gmail.com>
Date:   Thu Dec 12 09:28:57 2013 -0800

    Merge branch 'payment-method-service' of git://github.com/huoxito/quickbooks-ruby into huoxito-payment-method-service

    Conflicts:
    	lib/quickbooks-ruby.rb

commit 859811c79587420c95a9244e2cd07b56345f8679
Author: Washington Luiz <huoxito@gmail.com>
Date:   Wed Dec 11 23:40:57 2013 -0300

    Add PaymentMethod service

commit 9e591e288492cc1c1e9856a838dd1b2b92db1b1c
Author: Washington Luiz <huoxito@gmail.com>
Date:   Wed Dec 11 23:40:11 2013 -0300

    Construct all query insise BaseService#url_for_query

    Help us test queries with query strings. Otherwise we could get query
    not registered by FakeWeb since the query is being constructed in more
    than one place and we don't have access to that within net helper

commit 909fbc20ac4616a14ee7f90ac0fe240244f04241
Author: Washington Luiz <huoxito@gmail.com>
Date:   Wed Dec 11 22:08:45 2013 -0300

    Add TxnDate accessor for SalesReceipt