TVPaint: Match renderlayer key with other hosts

[iLLiCiTiT]

Brief description

Render layer key in TVPaint implementation is without underscode (render_layer -> renderlayer).

Description

Add 'renderlayer' to instance.data for TVPaint render instances. Render passes had render_layer which was changed to renderlayer and layers pass their variant as value. This is to match Maya specifically. There is a secondary reason to do so, to match subset group name filtering. Also usage of render_pass was modified to use renderpass to keep consistency.

Additional info

For some time there must be bost ways how are keys stored. Release variant of PR.

Testing notes:

• New files

1. Open new TVpaint file
2. Create some render layers/passes
3. Publish
4. All should work and if subset group profile is matching, it should be grouped

• Old files

1. Open TVPaint file with instances created before this PR
2. publish
3. All should work and subset groups should match too

[ynbot]

Task linked: OP-3132 TVP: group name in loader