Assert in copy_nodes_and_elements
Assert in copy_nodes_and_elements

If we try to copy an invalid partitioning then we get much more
confusing assertions later

hrittich/libmesh,dschwen/libmesh,giorgiobornia/libmesh,90jrong/libmesh,dschwen/libmesh,90jrong/libmesh,giorgiobornia/libmesh,BalticPinguin/libmesh,libMesh/libmesh,BalticPinguin/libmesh,BalticPinguin/libmesh,jwpeterson/libmesh,jwpeterson/libmesh,roystgnr/libmesh,dschwen/libmesh,hrittich/libmesh,libMesh/libmesh,giorgiobornia/libmesh,libMesh/libmesh,jwpeterson/libmesh,roystgnr/libmesh,jwpeterson/libmesh,hrittich/libmesh,hrittich/libmesh,hrittich/libmesh,pbauman/libmesh,giorgiobornia/libmesh,90jrong/libmesh,roystgnr/libmesh,libMesh/libmesh,capitalaslash/libmesh,hrittich/libmesh,jwpeterson/libmesh,jwpeterson/libmesh,giorgiobornia/libmesh,jwpeterson/libmesh,jwpeterson/libmesh,libMesh/libmesh,BalticPinguin/libmesh,pbauman/libmesh,90jrong/libmesh,dschwen/libmesh,pbauman/libmesh,capitalaslash/libmesh,dschwen/libmesh,giorgiobornia/libmesh,pbauman/libmesh,hrittich/libmesh,dschwen/libmesh,pbauman/libmesh,90jrong/libmesh,libMesh/libmesh,BalticPinguin/libmesh,pbauman/libmesh,libMesh/libmesh,capitalaslash/libmesh,pbauman/libmesh,hrittich/libmesh,roystgnr/libmesh,90jrong/libmesh,capitalaslash/libmesh,roystgnr/libmesh,90jrong/libmesh,capitalaslash/libmesh,giorgiobornia/libmesh,roystgnr/libmesh,giorgiobornia/libmesh,BalticPinguin/libmesh,BalticPinguin/libmesh,90jrong/libmesh,libMesh/libmesh,BalticPinguin/libmesh,pbauman/libmesh,roystgnr/libmesh,roystgnr/libmesh,capitalaslash/libmesh,90jrong/libmesh,pbauman/libmesh,dschwen/libmesh,capitalaslash/libmesh,capitalaslash/libmesh,hrittich/libmesh,giorgiobornia/libmesh,dschwen/libmesh