And instead implement it ourselves.

This solves a bug with that plugin whereby the connection handlers are
added to early and are therefore never fired.

Also fixed a problem whereby entity items are queried for features
before the features have been fetched.

so that it's applied in all cases where archived messages are fetched.

instead of wrongly checking the bare JID

Otherwise the model gets removed mid-creation, which causes the
`url required` error from Backbone.

So that we can call `getDisplayName`

Instead of saving the vcard data on the contact model itself

VCards will now always be used.

and not via the chatbox view (fixes some failing tests also).

- Refer to VCards instead of Avatars where appropriate
- Fetch VCards for non-groupchat messages as well

Entity items weren't being fetched from cache.

Apparently this bug only surfaced because with Ejabberd the upload
service is nested one level deeper than with Prosody.

we don't yet have a connection then, so listen to
`connectionInitialized` instead.

so that `hidden` class gets applied to the right element

- Filter did the opposite of what it was supposed to do
- Wrong bind context
- Should actually be mam:2, issue was server misconfiguration

if the fullname is not available.

This allows us to cache them for longer.