[NTG-context] New module: pararef

Hallo, after so many of you helped me, I want to give back. I just made my t-pararef module public for everyone: http://modules.contextgarden.net/pararef http://wiki.contextgarden.net/Paragraph_Referencing Please feel free to send me comments about the coding style and what I could have done in a better way. E.g. the interface file is missing, but I don't know how it should look like. But I hope mainly that it will prove beneficial for some of you. H.