Does not handle filepaths with multiple '-' in them

[rigred]

Filepaths such as file-name-something-400x300.jpeg group original would only match up to something

Possible fix to allow regex group original to capture such paths involves changing the regex in DefaultMutator to the below:

protected static $regexp = "/(?<original>[^-].+)-(?<size>(?<width>\d*)x(?<height>\d*))-?(?<signature>[0-9a-z]*)/";

This matches paths in much less time than the old regex too.
This is just a quick and simple fix I implemented, I am by no means a regex expert.