Travis-CI failure: python 3.5 segmentation fault about hydrofunctions

[mroberge]

I required typing==3.6.4 and this didn't affect the errors in my 3.5 build #186 from the segmentation fault described above in 184.2. See commit e587fb5

[mroberge]

I updated the Develop branch with the following fixes in commit bd30b73:

• don't upgrade from Pandas 0.22.0 to 0.23.0
  - runs with Pandas 0.23.0 included ended with RecursionErrors
  - using the old Pandas fixes the Python 3.6 build
  - Python 3.4 never used Pandas 0.23.0, and it was always able to build.
  - Python 3.5 still doesn't pass: It now reaches the tests though, but gets a segmentation fault.
• Don't test for Python 3.5
  - python setup.py test errors out due to a Segmentation Fault (described above)
  - pytest errors during tests because it can't import matplotlib.

You can see the results in TravisCI build #190

I'm still working on this issue in the require-old-pandas22 branch.
The remove-draw-map branch wasn't successful at fixing anything. It can be deleted.

[mroberge]

I finally resolved this issue by not including Seaborn and Bokeh in my build. I have no idea why this worked; the errors never mention seaborn.