Make clearer that usernames are published and sent to public bodies

[RichardTaylor]

At WhatDoTheyKnow we are seeing users who have signed a response with a pseudonym in the message body surprised that their username is shown on the request thread and sent to the public body.

The recent apparent emergence of this issue may relate to us reaching a different demographic of user.

Update the help page section on names:

https://www.whatdotheyknow.com/help/privacy#Names

to make clear usernames are published and sent to public bodies (even if an alternative name is used to sign off a message in the message body)

[RichardTaylor]

Related Alaveteli issue mysociety/alaveteli#6154

[RichardTaylor]

From WDTK support discussion in relation to a case today. An admin thought that a user: "perhaps doesn't realise that the user name on the account is published as well as the name that you sign off with".

[garethrees]

improved in mysociety/alaveteli#6154