Remove loadAppScriptFile

This removes `loadAppScriptFile` and enforces the usage of proper routing.

Fixes https://github.com/owncloud/core/issues/9060

# Todo

- [x] core
- [x] files
- [x] files_encryption
- [x] files_sharing
- [x] files_trashbin
- [x] files_versions
- [x] user_ldap
- [x] user_webdavauth
- [x] Create PR for some apps in the apps directory  (some examples: https://github.com/owncloud/apps/pull/1894)
- [ ] Send mail to developer ML

# Script to generate routes
```php
<?php

$app =  $argv[1];

$routableFolders = array(
	'ajax'
);

foreach($routableFolders as $folder) {
	$scannedDirectory = scandir('./'.$app.'/'.$folder);
	$scannedDirectory = array_diff($scannedDirectory, array('.', '..'));

	foreach($scannedDirectory as $file) {
		$fileWithoutExtension = substr($file, 0, -4);
		echo('$this->create(\''.$app.'_'.$folder.'_'.$fileWithoutExtension.'\', \''.$folder.'/'.$file.'\')'."\n");
		echo("\t".'->actionInclude(\''.$app.'/'.$folder.'/'.$file.'\');');
		echo("\n");
	}
}
```