SALTO-5643: Adding members in the order they are defined

[yelly]

Instead of adding new fields, annotations or values at the end of their parent in NaCl files, add them in the order they are defined in their parent object. This will ensure that members always show up in the same place in the NaCl if they are removed and added again.

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Additional context for reviewer
Still need to add higher level tests, IMO it's cleaner to split into a separate PR.

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Release Notes:
Core

• Element members (field, annotations or values) are added in the same location consistently instead of being appended.

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User Notifications:
None.

[coveralls]

coverage: 93.912% (-0.01%) from 93.923%
when pulling 4a28c0d on yelly:SALTO-5643
into 2d1d46b on salto-io:main.

[ori-moisis]

didn't finish reviewing the logic, but I think there are enough comments to do a round...