repository: needs full documentation update (and new binary instructions)

[rafaeldtinoco]

Now that the repository has a new golang binary tool to update the new kernels, documentation should be updated. Other documentation tasks needed:

1. Update all documentation files (check examples, distro versions, etc)
2. Update BPF/BTF internals documentation (btfgen was moved to bpftool)
3. Bring examples directory back with simple example on how to use this

[rafaeldtinoco]

Im still missing bringing the example back to the repository.