`TExternalResourceReader`
pt		GetExtensions
pt		GetDescription
pt		Load
pt		CheckMagic
		Create
		Destroy

`TAbstractResourceReader`
pt		SetDataSize
pt		SetHeaderSize
pt		SetDataOffset
pt		SetRawData
pt		CallSubReaderLoad
pt		AddNoTree
pt		GetTree
pt		GetExtensions
pt		GetDescription
pt		Load
pt		CheckMagic
		Create