Cross-compilation support

[Corentin-Gauthier]

Summary
Nimjl crashes when trying to get Julia version from a different architecture toolchain.

Description
I want to cross-compile a program for an aarch64 target on an x86 host. I have downloaded the Julia aarch64 toolchain and updated JULIA_PATH. The nimjl library crashes when it tries to get the Julia version with <JULIA_CROSS_TOOLCHAIN_DIR>/bin/julia -E VERSION. I have found a workaround by statically setting my version: installed in (config.nim) : const cmdOutput = "v\"1.10.6\"".

Alternatives
Get Julia version by parsing the name of <JULIA_CROSS_TOOLCHAIN_DIR>/lib/julia.so.<VERSION> or use another method that allows cross-compilation for multiple architectures ?

[Clonkk]

Ah indeed, this is highlighted in this comment

const cmdOutput = "v"1.10.6"".

This works as a workaround. You can also setup a CI in aarch64 so that the compiling environment matches the execution.

The proper solution will probably a define switch to match the aarch.

[Clonkk]

Tentative fix in #55

I would also make sure you have enough RAM to run Julia code on an aarch64 platform that doesn't compile locally.