add molecular clock to augur

[replikation]

• add params for --clock-rate {params.clock_rate} \
• https://nextstrain-augur.readthedocs.io/en/stable/usage/cli/refine.html
• annual evolution rate of 1.24 x 10-3 substitutions per site for SARS-CoV-2

[replikation]

alternatively set up a pre-configured next strain downstream process (?)