PLT-1527 Add a slash command to set yourself away (#3752)

* added handlers for slash commands

* added manual status persistance

* added tests

* removed extra debug output and comments

* rebase - fixing the PR

* making echo messages after slash commands ephemeral

api/post.go

@@ -679,7 +679,7 @@ func sendNotifications(c *Context, post *model.Post, team *model.Team, channel *
 			var status *model.Status
 			var err *model.AppError
 			if status, err = GetStatus(id); err != nil {
-				status = &model.Status{id, model.STATUS_OFFLINE, 0}
+				status = &model.Status{id, model.STATUS_OFFLINE, false, 0}
 			}
 
 			if userAllowsEmails && status.Status != model.STATUS_ONLINE {
@@ -727,7 +727,7 @@ func sendNotifications(c *Context, post *model.Post, team *model.Team, channel *
 			var status *model.Status
 			var err *model.AppError
 			if status, err = GetStatus(id); err != nil {
-				status = &model.Status{id, model.STATUS_OFFLINE, 0}
+				status = &model.Status{id, model.STATUS_OFFLINE, false, 0}
 			}
 
 			if profileMap[id].StatusAllowsPushNotification(status) {
@@ -740,7 +740,7 @@ func sendNotifications(c *Context, post *model.Post, team *model.Team, channel *
 				var status *model.Status
 				var err *model.AppError
 				if status, err = GetStatus(id); err != nil {
-					status = &model.Status{id, model.STATUS_OFFLINE, 0}
+					status = &model.Status{id, model.STATUS_OFFLINE, false, 0}
 				}
 
 				if profileMap[id].StatusAllowsPushNotification(status) {