Implementation of mime.store.IMimeStore interface that uses MEDIA/SUBTYPE.xml files from mime/ subfolder to read MIME types. It does not read any MIME type definitions at the construction time. Instead MediaSubtypeXmlStore performs parsing of separate files on demand when calling mimeType or byMimeType. All parsed definitions are getting cached to avoid re-parsing on every demand.
MIME store implemented around reading of various files in mime/ subfolder.