Malware Scanner: Scan for files for know dangerous contents

This class can scan for files for know dangerous contents.

It can traverse recursively a given directory and scan files that match a given file name pattern.

The class can scan the file contents to check if they contain given dangerous file content patterns.

If such content patterns are found, the class can repair the files by replacing the dangerous content by the correct data.

Optionally the class may fix the scanned file permissions to make them writable by all users.