MagFieldElements : move large inline function to .icc, format, tidy

...Field/MagFieldElements/MagFieldElements/AtlasFieldCache.h

...eld/MagFieldElements/MagFieldElements/AtlasFieldCache.icc

...icField/MagFieldElements/MagFieldElements/AtlasFieldMap.h

...eticField/MagFieldElements/MagFieldElements/BFieldCache.h

...icField/MagFieldElements/MagFieldElements/BFieldCache.icc

...icField/MagFieldElements/MagFieldElements/BFieldCacheZR.h

...Field/MagFieldElements/MagFieldElements/BFieldCacheZR.icc

MagneticField/MagFieldElements/MagFieldElements/BFieldCond.h

...ticField/MagFieldElements/MagFieldElements/BFieldCond.icc

MagneticField/MagFieldElements/MagFieldElements/BFieldMesh.h

...ticField/MagFieldElements/MagFieldElements/BFieldMesh.icc

...ticField/MagFieldElements/MagFieldElements/BFieldMeshZR.h

...ticField/MagFieldElements/MagFieldElements/BFieldVector.h

...cField/MagFieldElements/MagFieldElements/BFieldVectorZR.h

MagneticField/MagFieldElements/MagFieldElements/BFieldZone.h

MagneticField/MagFieldElements/src/AtlasFieldCache.cxx

MagneticField/MagFieldElements/src/AtlasFieldMap.cxx

MagneticField/MagFieldElements/src/BFieldMeshZR.cxx