devel/libayatana-appindicator: Add new port

Reviewed by: koobs@

Ayatana Application Indicators (Shared Library)

A library to allow applications to export a menu into the an Application
Indicators aware menu bar. Based on KSNI it also works in KDE and will
fallback to generic Systray support if none of those are available.

This code project was originally started by Canonical Ltd. and has been
adapted by various authors with the purpose of making this Application
Indicators available on Ubuntu and non-Ubuntu systems alike.

WWW: https://github.com/AyatanaIndicators/libayatana-appindicator