Improve cert details for SMIME / CRL Fetching

Authored by aheinecke on Jan 10 2018, 9:21 AM.

Description

Improve cert details for SMIME / CRL Fetching

This makes the key update for certificate details async as
it can take a while especially for SMIME with CRL's. While
the key is updated there is a placeholder displayed in the validity.

The validity is now also shown for S/MIME.