[REQ] Change Threat Library to ThreatClassic2

[aapoalas]

ThreatClassic-1.0 library is pretty much abandonware at this point. ThreatClassic2 has risen to take its place. The TC2 library has some of the long-known fixes for TC-1.0 and looks to be slated for active development as well.

Switching over would be a no-brainer. It might require a major version bump though, since different threat library versions cannot communicate with each other.