File _patchinfo of Package patchinfo

<patchinfo incident="10253">
  <category>optional</category>
  <rating>low</rating>
  <packager>sbahling</packager>
  <description>This update for perl-Class-Date, perl-Test-Warnings fixes the following issues:

- Add perl-Class-Date and dependencies to Backports:SLE-12
  This is to compensate for the fact that we removed the perl-Class-Date package
  from SLE 12. It was available in SLE 11 SDK.
</description>
  <summary>Optional update for perl-Class-Date, perl-Test-Warnings</summary>
</patchinfo>