AMVR (formely IMV) now has only one mode, which used to be mode #2
- remove SPS imv_mode parameter
- remove encoder configuration for mode #1 (mode #2 replaces mode #1)
- adapt config files to refer tp mode #1
- rename SPS syntax elements and access functions to AMVR

Note: IMV to AMVR renaming in other parts of the software should be done by proponents.

- The M0297 zero-out is also supported for SBT now.
- The zero-out scanning code is moved out of residual_coding_subblock.

Fix of the DQP signaling when there are multiple luma TUs in Single Tree and there is only one TU containing all of the chroma information

- all elements of SPSNext are moved into SPS
- syntax elements of SPS are sorted according to draft (as far as possible)
- comments were added where software and draft diverge

Remove unused contexts and split intra mode contexts into luma and
chroma sets to align with text description

There is a conflict with JVET_M0427_INLOOP_RESHAPER that is triggering a debug assertion that checks that the width is not 1.

- sps_sao_enabled_flag
- sps_alf_enabled_flag
- pcm_enabled_flag
- pcm_sample_bit_depth_luma_minus1
- pcm_sample_bit_depth_chroma_minus1
- log2_min_pcm_luma_coding_block_size_minus3
- log2_diff_max_min_pcm_luma_coding_block_size
- pcm_loop_filter_disabled_flag
- sps_ref_wraparound_enabled_flag
- sps_ref_wraparound_offset
- sps_temporal_mvp_enabled_flag
- sps_sbtmvp_enabled_flag
- sps_bdof_enabled_flag

Move the gtr2 flag (the abs_level_gt3_flag in text) after the par_level_flag in the first coding pass

removed binary decision tree (seems to be a bit of an overkill at this stage of the project) as a preparation for the integration of M0421

removed binary decision tree (seems to be a bit of an overkill at this stage of the project) as a preparation for the integration of M0421