Provide a @all alias shorthand for notifying everyone about a reply

[madduck]

In rare occasions, it makes sense to notify everyone in a reply, and instead of listing all names, it would be good to be able to use e.f. @all to achieve the same.

[robguthrie]

Is that everyone in the thread or the group? Would @thread and @group be suitable replacements for all? they could show up in autocomplete when @ALL was typed

[madduck]

Yes, I think having those would be better, as @all can be misleading.

[scheals]

Is this something still that has to be done?

I came here from CodeTriage, apologies in advance if I did something against the etiquette of this repo.

[robguthrie]

@scheals yes. We could still benefit from this