Rootio tchain scanner

Created by: maloft

Hello, There are many errors in the next proposition, but the idea is to add an argument to the loadEntry method : totalEntries. totalEntries is the total number of entries of the chain. This, i think, will allow to increase the nevbuf (number of entries in the basket) in order to be able to scan a chain containing more than one tree. Is it a way according to you ? Thanks