Collect number of interactive login sessions for netdata

This plugin collects a number of currently logged-in users (from uptime shell command), this metric is missed from core netdata.

Manual install

• copy plugin to python.d plugins dir
• copy config to /etc/netdata/python.d/
• restart netdata, check "logins" section

Configuration

As usual, no config is required by default

• to disable plugin, set command to /bin/false
• to change check interval, set update_every

Compatibility

Tested on Centos 7 and Suse SLES 11. As of netdata 1.10 python.d.plugin is not compatible with SLES 11 without some patching (see RPM spec in nearby repo for details).