Automate Telegraf installation for all hosts in infrastructure

Telegraf needs to be installed everywhere with the press of a button. But besides copying a config file, we need some careful customisation.

• Have a base config file for each platform
• add/remove lines in the config file depending on the server hostname. For example:
  • vmbuilder: monitor the Coin processes
  • ace-fawn etc: monitor the KVM processes
  • etc (TODO fill in)
• modify systemd unit files to run as root

EDIT:
We need to have

• configuration management system
• configuration management database (optional but would be good, in order to store all the information of the different hosts)
• new repository other than coin-secrets