Add utility function to get certificate from file
Add utility function to get certificate from file

This can be used to get our own certificate, for use in the
multimanager membership establishment.

xcat2/confluent,xcat2/confluent,jjohnson42/confluent,xcat2/confluent,jjohnson42/confluent,whowutwut/confluent,jjohnson42/confluent,jjohnson42/confluent,whowutwut/confluent,whowutwut/confluent,xcat2/confluent,whowutwut/confluent,jjohnson42/confluent,xcat2/confluent