- tiles are in the VVC spec for 3 meeting cycles now
- cleanup helps with adaptation for tiles to current draft

VTM version 4.2

includes:
- rename flag HandleCraAsBlaFlag to HandleCraAsCvsStartFlag
- changes of NAL unit types (reduced number)
- profile_tier_level and general_constraint_info structures

- remove duplicate ALF parameters from Slice
- add activation (to avoide overwriting when a new APS arrives)
- rename macro

keep max TU in #define for possibility of keeping the parameter

TU max/min size are constants in the VVC draft. Reflecting this in the software.

Merge functionality from HM (macro JCTVC_Y0038_PARAMS). Add an additional
configuration file parameter that allows re-sending parameter sets at every
random access point.

compositeRefEnabled is an encoder only option. It should not be stored in the SPS.
This commit is the last to remove unused parameters from SPSNext. Thus also
all comments related to SPSNext are removed.

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.

- 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

 - CE9.2.1g + RefinedMV only for MC and TMVP + SAD cost

- 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

Adding support for chroma sample location type 2 in CCLM