Added files that will be copied during the build of the application for Linux.

dist/linux/usr/local/share/applications/gui-for-ffmpeg.desktop

@@ -0,0 +1,9 @@
+[Desktop Entry]
+Type=Application
+Name=gui-for-ffmpeg
+GenericName=GUI for FFmpeg
+Exec=gui-for-ffmpeg
+Icon=gui-for-ffmpeg
+Comment=A simple interface for the FFmpeg console utility.
+Categories=AudioVideo;Utility;
+Keywords=ffmpeg;media;convert;transcode;audio;video;конвертер;видео;аудио;кодек;