new grouping API

src/CMakeLists.txt

src/core/peptidematch.cpp

src/core/peptidematch.h

src/core/proteinmatch.cpp

src/grouping/groupingexperiment.h

src/grouping/groupingpeptidemass.cpp

src/grouping/groupingpeptidemass.h

src/gui/peptide_list_view/peptidetablemodel.cpp

src/gui/protein_list_view/proteintablemodel.cpp