Big thanks !There is a wool-mod on terasologyforum.de (Link). I've tested it with the latest build and it works.
You must copy the files in the specific folder of your terasology.jar (block/blocktiles).
Console Commands: /giveBlock "ID"
ID's: Red, Green, Blue, Black, Yellow, Grey, Pink, Purple, DGreen, LGreen, White, LBlue