build: add more build options; obviates fastjet-feedstock patch for passthru submodule

[lgray]

• applies and improves a patch from conda-forge that allows a passthru-patch to the system-installed fastjet swig module
  • NB: it must have a different name from fastjet, anyone doing this manually will likely know how to do that (and fastjet has corresponding options)
  • allow user to set the system fastjet swig module name in the passthru import
• add an option for copying the gmp dll on windows