Bugfix: Static builds with '../' relative paths for objects do not build correctly.

Bugfix: Static builds with '../' relative paths for objects do not build correctly.

Add new function that handles converting the relative path with '../' with one that has no '../'.
Use this to build the object paths by adding the full relative directory path for the build files.

Note that this could be a problem with possible directory structure conflicts in some situations.

Utilize a new cache `cache_relative` for the processing of the relative path.

Add additional debug reporting to improve the error reporting details with the programs, like `ar`, fail.

Add note how future FLL versions (0.9 and later) should have something like `fl_path_canonical()`.

I need to also follow this commit up with an investigation to see if any of these `../` can get outside the project root.
There is a need for a project root parameter for situations where different paths are specified, such as specifying `--sources`.
Alternatively, I might have to restrict all `../` to the sources directory and then move all of my `tests/` directory files within the `sources/` directoreis for all projects.

This also gives me reason to consider adding IKI support to enhance the build settings.
I am on the fence on actually doing this or not.