channels.history has been deprecated

[samschlinkertcnn]

This week I got hit with an error trying to query channel history. Apparently the method has been deprecated in favor of conversations.history (more on the deprecation here).

I was wondering if that's an issue you're hoping to tackle soon, maybe easily? Or maybe I already can query that conversations.history method using the current version of this crate?

I do see that #99 and #101 have to do with adapting to changes in the Slack API. Maybe those large lifts will solve this issue (in which case you can feel feel to close this issue).

[samschlinkertcnn]

Ah, I see that @mettke's fork implements conversations.history, which will work for me for the time being (thanks!).

I'll close this issue now, as it's now really just a copy of #99.