When expanding the `{shared}` variable in a path like
`{shared}\shot\file.blend`, all slashes will be normalised to the target
platform, so for example result in:
- Windows: `Y:\shared\flamenco\shot\file.blend`
- Linux : `/shared/flamenco/shot/file.blend`
Due to this normalisation, the same paths will be served to these
platforms when the path was `{shared}/shot/file.blend`.
Simplify the code for the two-way variables' value-to-variable replacement.
Instead of using a goroutine and two channels, use a separate struct and
call a function on that directly.
No functional changes.