target broadcasting and numpy array support for generics

adresses #468 (closed)

• added target broadcasting for generics
• added support for numpy arrays as generic function return when those match the target frame in shape

-> i noted in the changelog.md there was already an entry stating broadcasting support was added already for flagGeneric: i didnt get into that, but a simple flagGeneric('v', func=lambda x: True) threw an exception complaining return type wasnt a series -> so didnt really work for the use case

CHANGELOG.md

@@ -8,7 +8,7 @@ SPDX-License-Identifier: GPL-3.0-or-later
 ## Unreleased
 [List of commits](https://git.ufz.de/rdm-software/saqc/-/compare/v2.5.0...develop)
 ### Added
-- `generics`: target broadcasting and numpy array support
+- `flagGeneric`, `processGeneric`: target broadcasting and numpy array support
 - `SaQC`: automatic translation of incoming flags
 - Option to change the flagging scheme after initialization
 - `flagByClick`: manually assign flags using a graphical user interface