Cleanup and perltidy.

Cleanup and perltidy.

Add "use warnings", remove unused variables and unnecessary finish/disconnect
at the end.  This script could be improved to run only on tables that need to
be altered instead of touching all of them.  It should also probably contain
warnings to the effect that it does not rescue your DATA that was forced into
whatever encoding the table used previously.

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