Add support for PHP 7 with default php.ini (short_open_tag=Off)

Replaced all "<?" with "<?php" except "<?=" which is always available since PHP 5.4.0. (Default behavior for PHP > 7.0.0)
Replaced each function with a for loop. (Deprecated since PHP 7.2.0)
Silence file_get_contents, if file doesn't exists
Replace define/defined to take string as argument
Silence rmdir & add default values for regtime, regip & orgacomment for lipsum plugin
Add .gitignore for generated files

Gargaj / wuhu