500+ warnings and a few errors on RTD and local

[tapaswenipathak]

Ref:

RTD

• https://readthedocs.org/api/v2/build/17828710.txt
• example: https://github.com/search?q=org%3AOpenMS+pseudocode&type=code

Local

[timosachsenberg]

todo: check out

fix warnings

and prevent building (exit code 1) if warnings are reintroduced