ENH: Added the ability to import GroupItemContents from CSV files
Also added an ItemView option to qtGroupItem to provide UI access to this new functionality:
<View Type="Instanced" Title="General">
<InstancedAttributes>
<Att Name="outputs-att" Type="outputs">
<ItemViews>
<View Path="/output-times" ImportCSV="true"/>
</ItemViews>
</Att>
</InstancedAttributes>
</View>