valid xml for all_object_info_totals_by_date

XML was invalid due to attempts to set the date as the XML element name.
Switch to array of date / count pairs.

New response example:
```
<?xml version="1.0" encoding="UTF-8"?>
<records type="array">
  <record>
    <date type="date">2010-11-11</date>
    <count type="integer">4</count>
  </record>
  <record>
    <date type="date">2010-11-30</date>
    <count type="integer">2</count>
  </record>
</records>
```
specify patchlevel for Ruby 1.8.7 tests
update CHANGELOG for returning valid xml