try to follow PEP8

- fixed most important code after checking with flake8
- ignored code which has to be reworked or removed
+ mark unused code with 'TODO: remove ...'

Change-Id: Ic45e541049e391e2853d29cd64bb0963bd9a2125
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/25053
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Enrico Faulhaber <enrico.faulhaber@frm2.tum.de>

secop/errors.py

@@ -22,7 +22,6 @@
 """Define (internal) SECoP Errors"""
 
 
-
 class SECoPError(RuntimeError):
 
     def __init__(self, *args, **kwds):