Bug 27192: Automatically set focus to the item type input box

Bug 27192: Automatically set focus to the item type input box

When adding a new item type, you have to click inside the
"Ιtem type:" input box before you can start entering text.

This patch fixes that by adding the "focus" class to the relevant
<input> element so that cursor focus is set when the page loads.

Test plan:

1) Try to add a new item type: notice how you have to manually
   click inside the "Item type:" input box before you start typing.
2) Apply this patch.
3) Repeat step 1) -- this time the "Item type:" input box should
   gain focus automatically.

Signed-off-by: Kelly McElligott <kelly@bywatersolutions.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>