DerivationFrameworkMuons clean up and LowPtMVA fixes

Hi this MR,

makes several changes to the DerivationFrameworkMuons in order to make https://gitlab.cern.ch/atlas-mcp/MuonPerformanceAnalysis/-/merge_requests/128 run, which is the central code of MCP to obtain the efficiency and momentum calibrations. Most of the changes in DerivationsFrameworkMuons are of stylish nature or insertion of smart pointers.

I also had to fix the MuonSelectionTool where the LowPtMVAEfficiency methods comes along with two short-comings:

• The method is inherently not thread-safe
• The muon->muonSegment(i) return nullptr although muon->nMuonSegments()` suggests validity. I am adding the muon software experts @nkoehler, @wleight here. May be they know why the segments are not properly written in the AODs

Also adding as MCP conveners: @mvanadia, @gartoni, @mkbugge, @dcieri and our well admired friend the @atlasbot.

It's a new MR and we have to continue the series philosopher of the day to make @goblirsc and the tracking group happy