Rework Crystal-SMD & THT generators to work with YAML

This is a complete rework of the crystal generators. It merges the SMD and THT generators into Crystals_Resonators , but SMD and THT have different YAML files. The updated generator is based on FootprintGenerator, hence it allows using -o output-dir etc.

In the future, the YAML files deserve some sorting, merging and inheritance.

I have manually verified that all files being generated are identical (including, not missing any files).