Enable quests to set multiple tags instead of just a single one

[pqhf5kd]

Can a quest ask a user for two values and modify two keys?

For example, I have just submitted a quest request in #70. kerb=* is fine for many crossings. In my country, it is common to have a crossing with a lowered kerb one side and a normal kern the other. There are keys kerb:left and kerb:right but I'm unsure how to integrate these into a quest.

[wtimme]

Sounds like a valid use case.

At the moment, an Answer only has a key and a value property. We could extend the modify the object to have a list of key-value pairs instead.

If someone wants to tackle this, I'm looking forward to your contribution.