Added FromJSON and ToJSON instances for Data.Tree.
Added FromJSON and ToJSON instances for Data.Tree.

The instances reuse the instance code for tuples.

aelve/json-x,sol/aeson,beni55/aeson,jkarni/aeson,timmytofu/aeson,23Skidoo/aeson,roelvandijk/aeson,neobrain/aeson,nurpax/aeson,plaprade/aeson,bwo/aeson,lykahb/aeson,dmjio/aeson,abbradar/aeson,SeanRBurton/aeson,sol/aeson,sol/aeson,roelvandijk/aeson,JPMoresmau/aeson,neobrain/aeson