init_jl_runtime does not work with Python ctypes

[tkf]

I find that loading .so file created by PackageCompiler.jl using Python ctypes is a bit tricky. It seems just calling init_jl_runtime() does not work.

Here is a MWE that works with Python ctypes. I had to call jl_init_with_image (or jl_init_with_image__threading) directly with the full path to the generated .so file:
https://gist.github.com/tkf/7a1b24ae13d01f417d616293db164b31

This version doesn't work. It calls init_jl_runtime() (and uses current master ded6405):
https://gist.github.com/tkf/d6562fc948b6418e82fb61560fd59719

It failed with:

ERROR: could not load library "/usr/bin/test.so"
/usr/bin/test.so: cannot open shared object file: No such file or directory

where /usr/bin/ was picked presumably because that's where my python executable is.

Both versions should be reproducible by just running make.

[KristofferC]

init_julia from the output of create_library should work. I tried it a day ago with ctypes.