[devel/protobuf] upgrade request to 3

[CeDeROM]

Hello,

I want to port Ultimaker Cura 2.3 to FreeBSD. This would bring 3D
print. However, Cura depends on CuraEngine and this depends on
protobuf >= 3.0.0. I think I have already asked for this upgrade some
time ago. Maybe there will be some spare time now to make the upgrade
please? :-)

Best ragards,
Tomek

-- 
CeDeROM, SQ7MHZ, http://www.tomek.cedro.info