Adding empty init file in the dagmc test dir.
Adding empty init file in the dagmc test dir.

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