Sync 0.3 and 0.4 release notes into README.md
Store the scanned $path in the DirectoryScanner

Will be useful in future to know the original path that the
DirectoryScanner is operating on, and this is cleaner than trying to
determine that from a filepath.
Add a $scanner variable to store the BaseScanner that initialized the Check

Will be useful to have a reference to the calling Scanner object, for
things like getting the original scan directory
Pass the Check a reference to the calling Scanner

So that the Check can see how it's being called
Add ClamAV Check

This Check runs ClamAV on the theme, scanning for any malicious files.
Enable ClamAVCheck on VIP Themes