Generated report is empty if email address is not fully configured

• Testcase included:

  yes

In one project, we have an otherwise correctly changes.xml, as verified by successfully running "mvn changes:changes-validate".

If I configure the author address as <author email="hakan.tandogan@gurkensalat.com" />, the generated report does not show any entries. If the author address is <author email="hakan.tandogan@gurkensalat.com">Hakan Tandogan</author> though, the same changes file shows the entries of changes.xml in the generated changes-report.html

An example project which demonstrates the behaviour is attached.