Building docs and running tests require install

[igoumiri]

Describe the bug
I'm not super familiar with Python projects but it seems very strange to me that the docs and tests reference the installed package rather that the local one.

To Reproduce
Steps to reproduce the behavior:

1. modify a file in /ssapy
2. build the docs or run unit tests
3. notice that the docs/tests don't reflect your changes

The workaround is to run python setup.py build and python setup.py install before step 2 but that's time consuming and error prone (easy to forget).

Expected behavior
I would expect the docs/tests to reflect my changes.

Output
None

Desktop (please complete the following information):
NA

Additional context
Not sure if it's a consequence of using setup.py (deprecated) to build/install. We should probably migrate to pip either way.

[aperloff]

We've been using the workaround for a while and I also suspect that it's needed because of how we use setup.py. We don't have a way to install a development version of SSAPy that references the local code rather than the installed version. I totally agree that we should migrate to pip. We just haven't had the person power to do that as of yet.

[SuperdoerTrav]

python setup.py develop used to work just fine for me to modify code in the environment.