[pve-devel] Add support for external graphite metric server

[Dietmar Maurer]

> Hi, this patches serie add support to send stats metric to an external
> graphite server.

I like the idea to support external monitoring tools, but I guess graphite
is not the only option. So maybe it is better to add some kind of plugin
system to support different tools. Something based on PVE::SectionConfig,
so that each plugin has its own configuration and code. What do 
you think?