Allow Python API to be used without h5py
Allow Python API to be used without h5py

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