TVPaint: switch layer IDs for layer names during identification

[iLLiCiTiT]

Description

TVPaint implementation used layer ids as unified identifier but it was found out that layer ids are not workfile persistent. Their ids may change if opened on different workstation, in that case all created instances and referenced containers loose track to source of their existence.

Changes

• layer ids are not used to be stored to metadata as identifiers of created instances or loaded containers
  • layer names are used instead which may not be consistent but are safer than ids
• this has few disadvantages
  • it is easier to loose track (e.g. on layer rename)
  • TVPaint allows to have multiple layers with same name so some validations are required
    • duplicated layer name validor was added, should care only for layer names that going to be published
• renamed filename validate_frame_range.py - > validate_render_pass_group.py as it never validated frame range
• change process order in reference loader on update
  • data about old layers are collected as first step then are removed with old container
  • then new container and new layers are inserted

🏴	this depends on
avalon-core	ynput/avalon-core#261