* Fixed mashing for even number of TOF bins.

[NikEfth]

Changes in this pull request

This PR fixes #1751. With even number of TOF abs, naive inversion does not work. If even we need to subtract 1.
Now, both -1 and 0 become a mashed TOF bin 0 but they have inverted detectors.

Testing performed

New tests introduced to explicitly check the transformation with even and odd TOF bins, with and without mashing.

Related issues

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[codacy-production]

Up to standards ✅

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🟢 Metrics 0 complexity · 6 duplication

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Duplication	6

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