Catalogue homogenisation incompatible with previous inputs

[mmpagani]

After enabling the tool to use uncertainty on magnitudes, the homogenization does not work with previous inputs.
@kejohnso

[kejohnso]

Oh no! Can you send me an example @mmpagani

[mmpagani]

Thanks @kejohnso I think I managed to modify the code to ensure back compatibility. I will prepare a PR during this week.