Fix Customer#password2 field name.

It looks like there's a typo in Customer. It seems to need "password2" instead of "password_2". It appears to be this way in the [2011](https://webservices.sandbox.netsuite.com/xsd/lists/v2011_1_0/relationships.xsd), [2012](https://webservices.sandbox.netsuite.com/xsd/lists/v2012_1_0/relationships.xsd), and [2013](https://webservices.sandbox.netsuite.com/xsd/lists/v2013_1_0/relationships.xsd) wsdls.

It fails if you try to set "password_2" and works like a charm if you use "password2".