Cleanup - admin scripts

Cleanup - admin scripts

Fixed useless redirect statements that weren't even printed.
Removed unused javascript and script variables;
Removed sth->finish.  Use get instead of post on "cancel" button (no data to post).
Reduce duplicative variables (e.g. scriptname and script_name).

Many other problems are still in the scripts, including use of META-REFRESH instead of
redirect, and the whole idea of redirecting back to the same page for no valid reason.
We should be able to formulate the right response on THIS pass, not ask the browser to start over.

Signed-off-by: Galen Charlton <galen.charlton@liblime.com>
Signed-off-by: Henri-Damien LAURENT <henridamien.laurent@biblibre.com>