Wip 9031 9262

Fixes for features 9031 and 9262
Add format support for rados ls
Improve test cases especially around namespace cleanup
With the current code if the caller does iter->get_nspace().c_str() the value of iter->get_nspace() is a temporary copy and so the memory for c_str() is getting deallocated.  On the other hand avoiding a copy has to be done carefully because ++iter can cause the string to change.  For general usage your suggested change is best.