Remove exceptions for elements missing in control block response

[jimmymcpeter]

For example, the following response to an old demo company:

<?xml version="1.0" encoding="UTF-8"?>
<response>
    <control>
        <status>failure</status>
        <senderid></senderid>
        <controlid></controlid>
    </control>
    <errormessage>
        <error>
            <errorno>PL04000055</errorno>
            <description></description>
            <description2>This company is a demo company and has expired.</description2>
            <correction></correction>
        </error>
    </errormessage>
</response>

will throw an exception because the uniqueid element is missing.