Group all copyright and author notices together.

libavcodec/alpha/simple_idct_alpha.c

libavcodec/armv4l/simple_idct_arm.S

libavcodec/bitstream.c

libavcodec/cyuv.c

libavcodec/dsputil.c

libavcodec/faandct.c

libavcodec/h263.c

libavcodec/huffyuv.c

libavcodec/i386/dsputil_mmx_avg.h

libavcodec/i386/dsputil_mmx_qns.h

libavcodec/i386/dsputil_mmx_rnd.h

libavcodec/i386/idct_mmx_xvid.c

libavcodec/i386/motion_est_mmx.c

libavcodec/i386/mpegvideo_mmx.c

libavcodec/ljpegenc.c

libavcodec/mdec.c

libavcodec/mjpeg.c

libavcodec/mjpeg.h

libavcodec/mjpegdec.c

libavcodec/mjpegenc.c