Add ProjectRenderer::getFileExtensionFromFormat.

Currently ProjectRenderer has a helper getFileFormatFromExtension, this adds a
similar helper getFileExtensionFromFormat.

This will, for example, return "ogg" for OggFile.

src/core/ProjectRenderer.cpp

@@ -124,6 +124,15 @@ ProjectRenderer::ExportFileFormats ProjectRenderer::getFileFormatFromExtension(
 
 
 
+QString ProjectRenderer::getFileExtensionFromFormat(
+		ExportFileFormats _fmt )
+{
+	return fileEncodeDevices[_fmt].m_extension;
+}
+
+
+
+
 void ProjectRenderer::startProcessing()
 {