HltTisTosAlg shouldn't throw an error when it can't find the trigger report of given name

We constantly have changing triggers, and in part of the data certain triggers didn't run. At the moment, this results in a stop of the algorithm:

HltTisTosAlgName_ce6ad35a             ERROR HltTisTosAlg::operator() : The HltDecReport for the line Hlt1LowMassNoipDielectronDecision is null. Please check!
HltTisTosAlgName_ce6ad35a             ERROR Maximum number of errors ( 'ErrorMax':1) reached.

This should be changed such that the user can define what they want to do in the tuple in case nothing is found.

@rowina @peilian