DLS patches

IpatchDLS2 — DLS version 2 instrument file object
IpatchDLSFile — DLS file object and functions
IpatchDLS2Info — DLS version 2 info functions and structure
IpatchDLSReader — DLS version 2 file reader
IpatchDLSWriter — DLS instrument file writer
IpatchDLS2Inst — DLS instrument object
IpatchDLS2Region — DLS region object
IpatchDLS2Conn — DLS version 2 connection structures and functions
IpatchDLS2Sample — DLS audio sample object
IpatchUnit_DLS — Unit types and conversions for DLS