Allow Greek questionmark for semi-colon

[simonpoole]

See https://twitter.com/mtmthemovie/status/1290018491089563648 in non-strict mode this might make sense as it could easily be used instead of a semi-colon.

[simonpoole]

Colons would also be a candidate see https://www.unicode.org/Public/security/latest/confusables.txt

[westnordost]

Found by accident:

"៖" is the colon equivalent in Khmer script

[westnordost]

FYI the Greek question mark ";" does currently not appear in any opening hours, collection times or service_times string on OSM.