Removed OpenCG geometry reference in openmc.mgxs.Library.__deepcopy__ routine
Removed OpenCG geometry reference in openmc.mgxs.Library.__deepcopy__ routine

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