Make quantile-generator accept multiple result files as input.
Make quantile-generator accept multiple result files as input.

sosy-lab/benchexec,dbeyer/benchexec,sosy-lab/benchexec,IljaZakharov/benchexec,sosy-lab/benchexec,dbeyer/benchexec,sosy-lab/benchexec,ultimate-pa/benchexec,ultimate-pa/benchexec,dbeyer/benchexec,dbeyer/benchexec,martin-neuhaeusser/benchexec,sosy-lab/benchexec,martin-neuhaeusser/benchexec,martin-neuhaeusser/benchexec,sosy-lab/benchexec,ultimate-pa/benchexec,martin-neuhaeusser/benchexec,IljaZakharov/benchexec,ultimate-pa/benchexec,IljaZakharov/benchexec,ultimate-pa/benchexec,ultimate-pa/benchexec,IljaZakharov/benchexec