Adding rpath support

[eulegang]

I'm not quite sure if this project wants to support it, but it would be a nice to have in my opinion.

[sdroege]

Thanks! This seems like a good idea, but instead of supporting specific linker arguments it would probably make more sense to pass through all -Wl arguments as-is to the linker. In addition to -rpath there's for example also -rpath-link which is quite useful to have.

Can you update the PR?

[eulegang]

Seems like a decent idea.

[eulegang]

Hopefully the ld_options is a suitable name. Something tells me it's not the worst idea to add it to the library struct for build scripts. If so something tells me we should also split the options by comma and with the -Wl, trimmed.

I'll update and worst case we strip it out.