Remove Zenoss.

there should be a cogent discussion on the removal of Zenoss from the awesome list

it doesnt support cri-o dockerless container monitoring,

kubernetes monitoring is NOT open source.

Azure monitoring is NOT open source

the last nginx zenpack monitor commit was 8 years ago.

it doesnt support MariaDB or galera cluster monitoring

the version of postgres it supports is 12 years old.

the source code for the postfix zenpack is a link to a 404

the HAProxy monitor is untested by the developer and hasnt seen a meaningful code commit in 3 years.