draughtsman installation should not require manual filling of values.yml

[calvix]

Current process with installing draughtsman is strange (described here - https://github.com/giantswarm/giantswarm/wiki/Draughtsman-Installation#install-draughtsman-chart)

1. prepare draughtsman values (config map an secret)
2. download helm package
3. untar helm package
4. replace values.yaml with values from config map + decrypted secrets
5. install helm package
6. create secret and config map draughtsman values to k8s cluster

I kinda miss the reason why we need to put the draughtsman values in two places and at this point, it doesn't work if we don't do that.

THis should be improved.