Implements skip_rest flag on the first band

Reduces the total number of symbols we have to code

video1-short:
           RATE (%)  DSNR (dB)
    PSNR -0.08130  0.00415
 PSNRHVS -0.07577  0.00561
    SSIM -0.06396  0.00291
FASTSSIM -0.12767  0.00727

subset1:
           RATE (%) DSNR (dB)
    PSNR 0.0163635 -0.000926524
 PSNRHVS 0.0184024 -0.00105508
    SSIM 0.0174851 -0.000821658
FASTSSIM 0.0242243 -0.000776809