fix issue #258
В роут API модуля добавлен необязательный параметр backend
Доработан скрипт генерации API ссылки
Исправлены ссылки на API контроллеры

Thx @wwhite
Added missing semicolon.
Added missing closing label tag.
Adding ADMIN_DIR_NAME to api request when is backend

Thx @wwhite
Removed SITE_URL and added Api.build_url
Fixed missing id= attribute.
Updated primary and foreign key values to be consistant with int(11).
Merge remote-tracking branch 'upstream/dev' into dev

Conflicts:
	cms/media/js/backend.js
	cms/modules/api/classes/api.php
	cms/modules/api/init.php
	cms/modules/elfinder/views/elfinder/filemanager.php
	cms/modules/elfinder/views/elfinder/manager.php
	cms/modules/page_parts/media/js/controller/parts.js
	cms/modules/pages/media/js/controller/page.js
	cms/modules/users/classes/kodicms/controller/users.php
	cms/modules/users/install/schema.sql
	cms/modules/users/media/js/controller/users.js
	cms/modules/users/views/users/edit.php
	cms/modules/users/views/users/profile.php
	cms/modules/widget/views/widgets/backend/page_menu.php