[salt.minion.cert] MySQL certificate and key

Adds ability to generate certificates and keys using
salt.minion.cert state for MySQL.

Usage:

Add the class to reclass model for db nodes:

classes:
 - system.salt.minion.cert.mysql.server

Apply state:
 salt 'db*' state.sls salt.minion.cert

PROD-14210
Change-Id: I8366dd618032c6179428ed5a25f59286fa518925
4 files changed