"fillTTree4Jet(TTree* t, Double_t* adresler, int index_VALID_jet)" : 
 * fills branches of the given TTree "t". "t" is a TTree that contains all the fields of type "Jet_VALID_ ...".
 * Values are taken from the "Jet_VALID_ ..." objects. Branches of "t" are filled with values like Jet_VALID_PT[i], where "i" is the index of the particle in a particular event.
 * 
 * "adresler" must be the same addresses that were used during the initialization of the "TTree" object.
 * 
 *  http://www.cplusplus.com/doc/tutorial/pointers/
 */