Catch exception thrown from sleep() in the Distributed watcher

Otherwise the exception would be printed when the process exits.

Author: JamesWrigley

src/DistributedNext.jl

@@ -142,7 +142,13 @@ function __init__()
             return
         end
 
-        sleep(1)
+        try
+            sleep(1)
+        catch
+            # sleep() may throw when the internal object it waits on is closed
+            # as the process exits.
+            return
+        end
     end
     errormonitor(watcher_task)
 end