AnalysisTop: Cleanup obsolete HL-LHC studies code

...is/TopPhys/xAOD/TopAnalysis/Root/EventSaverFlatNtuple.cxx

...Analysis/TopPhys/xAOD/TopAnalysis/Root/EventSelection.cxx

...s/TopPhys/xAOD/TopAnalysis/Root/EventSelectionManager.cxx

PhysicsAnalysis/TopPhys/xAOD/TopAnalysis/Root/Tools.cxx

...pPhys/xAOD/TopAnalysis/TopAnalysis/EventSaverFlatNtuple.h

...sis/TopPhys/xAOD/TopAnalysis/TopAnalysis/EventSelection.h

...Phys/xAOD/TopAnalysis/TopAnalysis/EventSelectionManager.h

PhysicsAnalysis/TopPhys/xAOD/TopAnalysis/TopAnalysis/Tools.h

.../xAOD/TopAnalysis/share/ART/artcut_test_410470afmc16a.txt

.../xAOD/TopAnalysis/share/ART/artcut_test_410470afmc16d.txt

.../xAOD/TopAnalysis/share/ART/artcut_test_410470fsmc16a.txt

.../TopAnalysis/share/ART/artcut_test_410470fsmc16apflow.txt

.../TopAnalysis/share/ART/artcut_test_410470fsmc16asysts.txt

.../xAOD/TopAnalysis/share/ART/artcut_test_410470fsmc16d.txt

...nalysis/share/ART/artcut_test_410470fsmc16dactualmurw.txt

...pAnalysis/share/ART/artcut_test_410470fsmc16dklfitter.txt

.../TopAnalysis/share/ART/artcut_test_410470fsmc16dpflow.txt

.../TopAnalysis/share/ART/artcut_test_410470fsmc16dsysts.txt

...nalysis/TopPhys/xAOD/TopAnalysis/share/example-config.txt

...alysis/TopPhys/xAOD/TopAnalysis/share/validation-cuts.txt