Update packaging for pip and conda installation

[kbseah]

Should resolve issue #25

The main changes were:

• Replace deprecated setup.py with pyproject.toml and fix module imports
• Add script as entry point that can be installed to path with setuptools
• Modify nuitka parameters and build.sh script to get Conda packaging working

I've tested (Linux only) both the local installation with the updated install.sh script, and building a Conda package tarball with the updated recipe. Both the interpreted and Nuitka-compiled versions were tested subsampled input files (see test-DnoisE/run_tests.sh). The compiled version gives an error with multi-CPU mode, but this issue was already present before this update.

It should now be possible to package and distribute the pure Python version via PyPI, while the Conda recipe can be used to distribute both the interpreted and compiled versions. I'd be happy to help with packaging for Bioconda.

[adriantich]

Thank you so much Brandon, I think that your changes really improve the program.

[kbseah]

Thanks Adri for this useful tool!