Rudder tools

For Rudder 4+ and 5.0, we have a functioning toolchain, a bit difficult to bootstrap, but still usable, that rely on syslog

For 5.1, we need to change everything, as:
- there are certificates for nodes
- reports are sent with https, and signed
- we still need to support syslog, to validate it still works, and compare HTTPS with SYSLOG

tsung is also too hard to use for our use case (replace placeholder in inventories)

1. Generate the certificates, and store them for signing later information
2. Generate inventories, with specific data per inventories: uuid, hostname, IP, mac, OS name, agent version, difference in softwares (a bit of randomness ?); include these data in the inventory, along with the certificate
3. Sign and send the inventory to the Rudder server
4. Read reporting data by rudder, and generate syslog reports, or plain text file, and sign and send these plain text file