Missing features and documentation for module php extensions and folderrights feature

[blackcoder87]

Back in 2016 someone implemented features for modules to "register" needed PHP extensions to be displayed on the PHP extensions info page and folders that need special rights on the folderrights page in the admincenter. These features are undocumented and their appears to be no functions to add entries. Entries can of course be added by directly using the querybuilder.

table: modules_folderrights
table: modules_php_extensions

• Add functions to add entries to these tables in the infos mapper.
• Write documentation for this features in the developer documentation.

Additional context
1cffe8c
https://github.com/IlchCMS/Ilch-2.0/blob/master/application/modules/admin/mappers/Infos.php

Ilch-2.0/application/modules/admin/controllers/admin/Infos.php

Line 97 in 1cffe8c

public function folderrightsAction()

Ilch-2.0/application/modules/admin/controllers/admin/Infos.php

Line 108 in 1cffe8c

public function phpextensionsAction()

https://github.com/IlchCMS/Ilch-2.0/blob/1cffe8cf0525ed52bd5a3ad40be4201c4d2e3b5b/application/modules/admin/views/admin/infos/folderrights.php
https://github.com/IlchCMS/Ilch-2.0/blob/1cffe8cf0525ed52bd5a3ad40be4201c4d2e3b5b/application/modules/admin/views/admin/infos/phpextensions.php
https://github.com/IlchCMS/Ilch-2.0/wiki/Doku-Entwickler