Nemesis: Don't put cmaps unless we have cmaps
Nemesis: Don't put cmaps unless we have cmaps

Neither I nor @jwpeterson nor the Nemesis manual seem clear on what
exactly these are *used* for, so although I suspect further changes
may be appropriate, I'm committing only the minimal changes that get
all the corner cases I can find working for me.

In the future we might consider putting all ghosted elements into the
elem cmaps, not just neighbor elements.

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