the ajax-processes can now be canceled
when the user clicks on the button the ajax-process is started and the
text of the button is prefixed with "Cancel ". now, when the user clicks
on the button again, the ajax-process is aborted and the text is
changing back to the old value.
i streamlined the javascript-implementation to reduce the
per-mod-generated javascript and the javascript code inside the
mod.class.php. currently i have no idea how to get the wordpress-i18n
into the admin_ajax-javascript.
Merge pull request #101 from csenf/ajax_cancel

the ajax-processes can now be canceled
less logging
added ajax resync logic

limit is set to 10, but each loop imports a whole month. this results
in a little confusing progress display, but works fine.
added count_items() function

it displays all the users tweets. not sure if we can get all of them
through the API.