votes: add canonize_district filter
votes: add canonize_district filter

Signed-off-by: Imre Deak <fbd5edba1988036c8923f0cca0cce6ac4811db29@gmail.com>

kansanmuisti/kamu,kansanmuisti/kamu,kansanmuisti/kamu,kansanmuisti/kamu,kansanmuisti/kamu