MultiArc helper utilities by Zharski 2003-12-23

MultiArc helper utilities.
There are some utilities that can be used as external archivers and was adapted by me to work with MultiArc. This is:
- UnLZX - that add support for reading Amiga's LZX files.
- uncompress - for reading UNIX-like Z-compressed files.
- HelpDeco - to browse contents of Windows HLP and MVB files.
- StgDoc - for work with M$ compound storages.