[Users] How do I create a WMS Capabilities Tree in GeoExt 2?

[Andrew Miller]

I am trying to create a WMS Capabilities Tree in GeoExt 2, similar to
this example:

http://api.geoext.org/1.1/examples/wms-tree.html

However that example uses WMSCapabilitiesLoader which has been removed
from GeoExt 2.  How do I achieve the same thing?

Thanks,

Andrew