idea: ability to specify ensure seconds

[jjb]

--- a/lib/better_timeout.rb
+++ b/lib/better_timeout.rb
@@ -64,7 +64,7 @@ module Timeout
             x.raise e
           else
             x.raise exception, "execution expired"
-            x.join
+            x.join(3.1)#(ensure_seconds) <-- this can be a feature of better timeout - option to give inner code ensure_seconds for ensure to finish
             current_thread.raise exception, "execution expired"
           end
         }