pidgin/purple-plugin-pack

Re-add purple2 compatibility with #if PURPLE_VERSION_CHECK(3,0,0) blocks

Based on previous commits between 2.7.0 and now, this is sorta like reverting
those changes partially.
[Ning Protocol Plugin]
type=broken
depends=purple json-glib
provides=ning
summary=Protocol plugin for the Ning social networking site framework
description=Protocol plugin for the Ning social networking site framework
authors=Eion Robb
introduced=2.7.0