Possible refine_and_coarsen_elements early return
Possible refine_and_coarsen_elements early return

This is a cheap test to add, but can save quite some time when users
call refine_and_coarsen_elements without having anything to refine or
coarsen.

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