Cannot create user at admin page

[sinsinpub]

Just for master branch, according the comment for latest commit of user_create.php file: 'Move create user form to its own page'. user_create.php has changed its workflow like other form page: 'If form.submit_form exists, then invoke function process_form()'. However there is NO hidden field 'submit_form' at all in the form constructed by function display_form(). After submitting the form, nothing will be done but displaying an empty one.

[sabas]

I believe I added the field.. Try the fix https://github.com/sproctor/php-calendar/blob/master/php-calendar/includes/user_create.php