commands: Make error on setting rlimit a warning only

And reduce it to 10000.

Closes #3582

commands/limit_darwin.go

@@ -75,11 +75,11 @@ func tweakLimit() {
 		jww.ERROR.Println("Unable to obtain rLimit", err)
 	}
 	if rLimit.Cur < rLimit.Max {
-		rLimit.Max = 999999
-		rLimit.Cur = 999999
+		rLimit.Max = 10000
+		rLimit.Cur = 10000
 		err = syscall.Setrlimit(syscall.RLIMIT_NOFILE, &rLimit)
 		if err != nil {
-			jww.ERROR.Println("Unable to increase number of open files limit", err)
+			jww.WARN.Println("Unable to increase number of open files limit", err)
 		}
 	}
 }