non-group-files will be loaded much faster now

since now, e.g. with tiff files, each and every file tried to examine all
files in the same folder to check whether there exists a metadata file
in the same directory. this check was performed on setSource,
even if m_groupfiles was disabled.

Signed-off-by: dietzc <christian.dietz@uni-konstanz.de>

org.knime.knip.io/src/org/knime/knip/io/ScifioImgSource.java

@@ -365,7 +365,8 @@ private Reader getReader(final String imgRef) throws FormatException,
 		}
 
 		if (!m_checkFileFormat || m_reader.getMetadata() == null) {
-			m_reader.setSource(imgRef);
+			m_reader.setSource(imgRef,
+					new SCIFIOConfig().groupableSetGroupFiles(m_isGroupFiles));
 
 			// NOTE: after an image (one series) is read once, the reader is
 			// closed by the ImgOpener (also setting the metadata to null).