New formats for layer creation

This is being already discussed in the opencadtools-devel mailing list:

https://joinup.ec.europa.eu/software/opencadtools/topic/opencadtools-devel-new-formats-layer-creation
https://joinup.ec.europa.eu/software/opencadtools/topic/opencadtools-devel-new-formats-layer-creation-creation-alphanumeric-tabl