Notes on How to Setup and Install Pyimfit

Current Local Procedure:

cd to top directory and build things
1. $ cd pyimfit_working
2. $ python3 setup.py uninstall; python3 setup.py clean; python3 setup.py develop

This is for other people; also for future testing purposes

Install necessary libraries: FFTW3, GNU Scientific Library (GSL), NLopt
1. Linux: install libraries using preferred package manager (Note: Be sure GSL is at least version 2.0!)
2. macOS: install libraries using preferred package manager. With Homebrew:
```
brew install fftw
brew install gsl
brew install nlopt
```
  If you will be using the default Apple/Xcode compilers, you also need to install the OpenMP library. With Homebrew:
```
brew install libomp
```
Install using pip (since PyImfit is Python-3-only, use pip3 unless the only version of Python you have is Python 3)
```
   pip3 install pyimfit
```

Update version number in pyimfit/init.py
Mac: Build source and binary distributions:
```
$ python3 setup.py sdist bdist_wheel
```

Mac: Edit wheel to include dynamic libraries

$ cd dist
$ delocate-wheel -w fixed_wheels -v pyimfit-<VERSION>-cp37-cp37m-macosx_10_9_x86_64.whl

Test uploading to TestPyPI (upload source-dist and modified wheel)

$ twine upload --repository-url https://test.pypi.org/legacy/ dist/pyimfit-.tar.gz dist/fixed_wheels/*

(To upload an updated version, specify the latest wheel file explicitly instead of "dist/*".)

Create a new virtualenv (see Installing Packages for detailed instructions) and install your package from TestPyPI:

$ pip install numpy scipy astropy ipython

$ pip install -i https://test.pypi.org/simple/ pyimfit-working

If things work OK, upload to regular PyPI:

python3 -m twine upload dist/pyimfit-.tar.gz dist/fixed_wheels/*

Note: Currently we do not attempt to build a binary wheel for Linux, since that's sort of a confusing nightmare.