MAINT: Move `Filter` classes from `constraints.py` to new `filters.py`
Closes #1300 (closed)
The motivation is described in the issue above (happy to have discussion).
On the user side, this is fully backward compatible, because all the moved Filter
classes are again imported in constraints.py
.
The documentation for the Filter
classes are separate out of "Constraints". The link to the Filter
classes is also added in the optimization page.