[collectd] Configurable naming_schema with ec2metadata support

[Michal Czerwinski]

Good day,

It would be nice to have configurable naming_schema with support to
read ec2metadata (reading single files from metadata directory), in
many cases these days having your stats aligned by hostname is not
good enough, I would be looking to have something like plugin/host and
in the cloud environment - plugin/security_group/instance-id. This
would be extremely useful.

Comments?

MC.