[otrs] Using accesskey

Hi OTRS folks, I used to press Enter to submit followups instead of clicking the form button. Now that there is the "Attach" button this doesn't work since the page gets just reloaded. Then I added the "accesskey" attribute to the HTML template: This way I can avoid clicking manually. I think it would be great to include this fix into the official distribution, along with accesskey specification for each link (ticket list, phone ticket, compose, standard replies, customer info etc.) to let people browse without the mouse. Keep up the good work! - Alessandro