[UX]Make admin setting links to point to the right section on admin page

We don’t have a relation between the admin settings link and the admin section it should point to.

For exemple, at tiki-admin_schedulers.php the wrench (go to settings) link to tiki-admin.php?page=general (the top) of the page. The url should direct to the Scheduler settings section and not just the page where it is for the user to search it.

I modified the block.title.php to add in the url the anchor it should go to (tiki-admin.php?page=general#scheduler) I added an id to the corresponding fieldset (fieldset id="scheduler") As fallback, in case there is no "id" (yet or missing) the behaviour will be the same as previously (it goes to the page)