Re-think how the generator should work.

[cedlemo]

the generator should build the dune files because:

• when parsing GO gir files, it determines the files to generate that depends on the lib versions
• if C stubs is to be used for constants, struct ..., dune files will have to be automatically generated. This can not be done manually.

Knowing this a new directory tree must be defined.

The actions to build the lib must be (is it even doable):

• create a bindings and dune generator
• use the dune file to build all.