Also removed mayavi from [all] (traits problem)

setup.cfg

@@ -66,11 +66,10 @@ colors =
 all =
     pyfftw
     cmocean
-    mayavi >= 4.7
 # TODO: pip install .[io] is not working because hyperspy depends on trait which has no wheels on PyPI at the moment...
-# TODO: FURTHERMORE, tvtk is apparently also a problem...
 # TODO: See https://github.com/hyperspy/hyperspy/issues/2315 and https://github.com/enthought/traits/issues/357
 # TODO: Add hyperspy back as soon (if?) this is resolved... Until then: install hyperspy with conda!
+# TODO: mayavi has the same exact problem and tvtk is apparently also a problem...
 
 # CONFIGURATION FOR TESTING: