domain_conf: Introducde virDomainObjListRenameAddNew() & virDomainObjListRenameRemove()
    
    We just need to update the entry in the second hash table. Since commit 8728a56
    we have two hash tables for the domain list so that we can do O(1) lookup
    regardless of looking up by UUID or name. Since with renaming a domain UUID does
    not change, we only need to update the second hash table, where domains are
    referenced by their name.
    
    We will call both functions from the qemuDomainRename().
    
    Signed-off-by: Tomas Meszaros <exo@tty.sk>