Remove src/apps/grid2grid.C.
Remove src/apps/grid2grid.C.

As far as I can tell, this app has never been built since we moved to
the automake build system, and it depended on the LegacyXdrIO class
which was removed a while ago. It was apparently only for comparing
against MGF solutions, and isn't really useful anymore.

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