Consider introducing generic veto-voter model in affmatching

[marekhorst]

This is a #1327 follow up.

One of the ways to refine the CommonAffSectionWordsVoter voter accuracy was checking for country code compatibility between affiliation and organization. This could be understood as a "veto-vote" (ack @mpol idea for this name) and could be promoted to a generic veto-voter solution on a higher level (e.g. part of the matcher).

Directly reffered in this comment thread:
#1337 (comment)