Not really good with grammar but looks like we are trying to change the field...

Not really good with grammar but looks like we are trying to change the field's label value here in code.

Also, current code is consistent with 7.x
http://cgit.drupalcode.org/clientside_validation/tree/plugins/validator/...

I feel we should aim at allowing these messages to be configurable. What do you say @Leon / @Jelle_S / @attiks?