increased max extrap length which caused fit failures if Y=9m
change hcal positioning, Z now centre of hcal
some minor cleanup
Merge branch 'master' of https://github.com/ShipSoft/FairShip
add some shielding for sens plane in 2nd det
update for muonShield, fix Hcal position via python
new formula totalLength= 2.5*Yheight+35*u.m plus minor mods