[FEATURE] Add redirect to login feature

Added option to redirect user to login page if he isn't
authorised when trying to access a file.

Example config to enable this:
$GLOBALS['TYPO3_CONF_VARS']['EXTCONF']['fal_securedownload']['login_redirect_url']
= '/login/?redirect_url=###REQUEST_URI###';
[TASK] Updated version to 0.0.4
[TASK] Show secured files in BE without FE login
[RELEASE] Version 0.0.4