Implemented the Mgxs objects member functions so now we can start replacing NuclideMG and MacroXS directly
Implemented the Mgxs objects member functions so now we can start replacing NuclideMG and MacroXS directly

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