Import of the RISC OS 4.02 version of !SndSetup (ie with VIDC support retrofitted). The following changes have been made:

* Renamed MkClean etc for consistency
* Removed obsolete (Phoebe) SetVolumes sub-component
* Stripped dependencies from makefile
* Added a VersionNum file (though this isn't used automatically)
* Fixed messages file:
  + application date was wrong format