config.nims hack prevents using nim c somewrapper from outside nimterop repo

[timotheecour]

soloud wrapper relies on cpp files, and it works when running from inside wrappers repo because of config.nims hack which redefines the linker; however it'll fail if main profile file is outside this repo since that config file won't be applied anymore and you'll get:

Undefined symbols for architecture x86_64:
  "std::terminate()", referenced from:
      ___clang_call_terminate in soloud.cpp.o
      ___clang_call_terminate in soloud_bus.cpp.o
...

workaround

• use nim cpp
• copy over/pass on cmdline the linker flags from config.nims

proposal

• build soloud into a shared library (or static lib, or both)
• optionally, maybe use the soloud-recommended build (which requires using genie, another dependency...)
• remove linker hack in wrappers/config.nims
• remove linker hack in nimterop/config.nims