We were using `yaml.Unmarshal` on basic types or inline structs. This
was not efficient and not clear to defined what we expect in labels.
We now use types to unmarshal the labels.
Only the `values` label is, at this time, parsed by GetValuesFromLabel
because this `utils` function is clearly a special case.
- changed variables that was uppercased, that's not OK for linters
- cleanup some documentation
- remove the "/" in label prefix, a function is now used to get the
complete label (`labelName()`)
- some cleanup in tpl files, and so on...
