Install openmc.h header properly
Install openmc.h header properly

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