Bug-fix on action list, now correctly checks for Acl on current user
do_action and action_completed now check for Acl before continuing
New alert.js.erb to show a generic message when a JS request fails
 Fixed partial views for actions
 Now it's possiblke to pass an "exclude" option to partial view "action" to hide some action buttons (pass the managers you want to hide)
 Added 'w' permission to the sign activity, to permit to modify the practice even when it's ready for sign