When using the gem externally, outside the specs, an IntuitRequestException will error with a:

`NoMethodError: undefined method `detail' for #<IntuitRequestException:0x007f96164af8b8>`

To reproduce this the Quickeebooks gem also included,
which is going to be a common scenario.

In short what is happening is that the IntuitRequestException from the
Quickeebooks class is taking over since it is on the global namespace.
That is why it doesn't recognize the `detail` method.

The fix is to put the exception handlers under the library's namespace.

Note: ClassUtili, only being used for conditionally checking of old
exception code has been now been removed.
Merge with master and fix conflict with lib/quickbooks/service/base_service.rb
Merge pull request #26 from minimul/exception-handling-error

Exception handling error
Initial progress in adding term and payment
Payment sparse update and deletion
Finishing up Term service and tests
Adding convenience methods and missing fixtures
Add validations to Payment and Term
Git outta here, Enumerable!
Update README
Fixing specs, adding to_xml on BigDecimal fields, and adding Model.new(attributes) support
Merge pull request #27 from harvesthq/adding_term_and_payment

Add Term, Payment, and an attributes accessor