Strength mime checking by comparing mime-type to the file path mime-type if we have...

Strength mime checking by comparing mime-type to the file path mime-type if we have entity_id and file id otherwise only permit image mime_types to be accepted if going via the filename route

Ensure mimetype is set in the case where we are passing it through and its valid

Remove Whitelisting of mime-types as not useful and only check mime-types if we have had one passed in