Clarify error messages when checking cell/lattice offsets
Clarify error messages when checking cell/lattice offsets

smharper/openmc,bhermanmit/openmc,bhermanmit/openmc,amandalund/openmc,johnnyliu27/openmc,mit-crpg/openmc,wbinventor/openmc,kellyrowland/openmc,lilulu/openmc,shikhar413/openmc,liangjg/openmc,samuelshaner/openmc,mit-crpg/openmc,samuelshaner/openmc,shikhar413/openmc,johnnyliu27/openmc,shikhar413/openmc,samuelshaner/openmc,liangjg/openmc,walshjon/openmc,paulromano/openmc,liangjg/openmc,walshjon/openmc,amandalund/openmc,walshjon/openmc,amandalund/openmc,johnnyliu27/openmc,smharper/openmc,wbinventor/openmc,lilulu/openmc,walshjon/openmc,liangjg/openmc,paulromano/openmc,shikhar413/openmc,wbinventor/openmc,paulromano/openmc,mjlong/openmc,lilulu/openmc,samuelshaner/openmc,smharper/openmc,paulromano/openmc,smharper/openmc,johnnyliu27/openmc,mjlong/openmc,kellyrowland/openmc,mit-crpg/openmc,mit-crpg/openmc,amandalund/openmc,wbinventor/openmc