Python 3.8 cannot install pyFAI 0.16

[JunCEEE]

https://travis-ci.org/github/PaNOSC-ViNYL/SimEx/jobs/731976398

ERROR: Failed building wheel for pyFAI 0.16

[JunCEEE]

The solution is to

• loose the pyFAI version restriction.

• update the deprecated analysis function.

• Lock the version of pyFAI.