net-mgmt/pmacct: update 0.14.3 -> 1.6.1

• take maintainership
• MongoDB support is still broken. Version 1.6.1 as well as 0.14.3 requires legacy 0.8.1 mongo-c-driver which is no longer available in ports tree.
• nflog support requires missing libraries, so it is disabled.
• Other features like RabbitMQ or Kafka should work.

PR: 217448
Changes: http://www.pmacct.net/ChangeLog-1.6.1
Submitted by: Alexander Shikov <a.shikov@itcons.net.ua>
Approved by: zi (maintainer)