Suppress "WARNING: unknown mimetype for ..." when building epub #3391
Suppress "WARNING: unknown mimetype for ..." when building epub #3391

Requires Sphinx 1.5.1 or higher per
https://github.com/sphinx-doc/sphinx/issues/3214

ekoi/DANS-DVN-4.6.1,JayanthyChengan/dataverse,JayanthyChengan/dataverse,ekoi/DANS-DVN-4.6.1,ekoi/DANS-DVN-4.6.1,jacksonokuhn/dataverse,jacksonokuhn/dataverse,ekoi/DANS-DVN-4.6.1,JayanthyChengan/dataverse,jacksonokuhn/dataverse,JayanthyChengan/dataverse,jacksonokuhn/dataverse,JayanthyChengan/dataverse,ekoi/DANS-DVN-4.6.1,JayanthyChengan/dataverse,jacksonokuhn/dataverse,JayanthyChengan/dataverse,ekoi/DANS-DVN-4.6.1,ekoi/DANS-DVN-4.6.1,JayanthyChengan/dataverse,jacksonokuhn/dataverse,jacksonokuhn/dataverse,jacksonokuhn/dataverse,ekoi/DANS-DVN-4.6.1