* Introducing a new way for the l1watcher thread using the ast_sched way. Now l1watch...

* Introducing a new way for the l1watcher thread using the ast_sched way. Now l1watcher timeouts can be configured separately for every portgroup.
* added a signal handler to allow waking up the misdn task thread (that may sleep in a poll call) via misdn_tasks_wakeup().
* overlap_dial functionality implemented.
* fixes a bug which leads to a segfault after reordering config elements in the enum or struct

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@37382 65c4cc65-6c06-0410-ace0-fbb531ad65f3