Sync payments changes membership status which are overriden

[eptbertram]

If you synchronize membership contribution payments, the end date and membership status will be adjusted. At least if "Extend membership when contribution is completed" is checked in the configuration.

There is no filter as to which status is excluded in https://github.com/Project60/org.project60.membership/blob/new_master/api/v3/MembershipPayment/AssignAll.php
In some installations, however, it is possible that an active status "Cancelled by the end of the year" has been set manually, permanently overriding the status. Syncing a payment sets this status to Current, but leaves it permanently overwritten. This is wrong.

Can a filter be installed that checks whether a status is permanently overwritten? In this case, the membership should not be updated, but only the link between payment and membership should be established.

As this is problematic from a technical point of view, we could at least refer to this constellation in the help text on the configuration page.

Any opinions on this issue?

[eptbertram]

This issue refers to:
#18
#49