Fixed issues with QMTests in Gen/GenTune for RIVET 2.7.x

Source code of test plugin needed some minor changes to avoid failling in QMTests due to warnings. I also removed the -g compilation flag as it had unwanted effects due to -O2 flag used by rivet-buildplugin. Also since RIVET native scripts seem to have solved the issues with picking up library paths, I switched GenTune to using these scripts and thus I removed the redundant script in bin directory.