Simulating the ANSTO Platypus instrument in McStas

Changes

20210622

  • add polarising mirror; not specified reflectivities yet, so not yet operational
  • add lambda0 and dlambda to parameter list
  • can select between FOC and POL
  • parameterise m-coatings for L/R on CG3

20210621

  • made Platypus part of CG3
  • validated geometry of CG3 + Platypus
  • updated documentation
  • updated source term`