* SerieHeader::AddFileName() creates as many Coherent Files lists

	* SerieHeader::AddFileName() creates as many Coherent Files lists
	              (same Serie UID) as it founds different Serie UID
					   amongst the files insead of discarting any file
						that doesn't match with the first one he found.
	* SerieHeader::OrderGdcmFileListhas now pne parameter :
	               the Coherent Files list the user wants to sort
   * SerieHeader::GetFirstCoherentFileList()
   * SerieHeader::GetLastCoherentFileList() allows to parse
	               the set of Coherent Files lists
   * const SerieHeader::GdcmFileList &GetGdcmFileList() is kept, for backwards
	               compatibility (it returns the *first* Coherent Files list,
						since there was only one before)