4.2.0

• Fix #3480: Function decorated with [<NamedParams>] without arguments provided should take an empty object

• Fix #3494: Calling an attached parametrized getter fails in transpiled javascript

• Remove fable-py support

• Fix #3461: Don't default to javascript if the language requested by the user is unknown (help detect typo)

• Improve --help message for the --lang section

• Fix #3464: Invalidate cache when the target language changes

• Always delete the fable_modules folder when the cache is invalidated

• Remove --typescript options support, use --lang <target> instead

• Fix #3441: Don't ignore error when loading plugin

• Fix #3482: Remove Py.python and Py.expr_python use emitPyStatement and emitPyExpr instead

• Restrict replacements to accept only functions from their target language module

• Fix #3528: Consider functions hidden by a signature file as private (@nojaf)

• Improve error message when Fable doesn't find the fable-library folder.

  This is especially useful when working on Fable itself, and should save time to others.
  Each time I got this is error, I needed several minutes to remember the cause of it.