Making it easier to spot TDs.json errors

[egekorkan]

Currently, one needs to put all the TDs of the Things of the system in an array. However, when these TDs are not correct in the sense that an affordance in the plantuml is not found, the following error is generated:

generateSD problem!: TypeError: Cannot read properties of undefined (reading 'forms')

This happens when an affordance cannot be found. It should be easy to log what this affordance is.