Each tool needs to be independent, which
meant that every time a tool was called,
it would build the entire system graph.
This was an obvious waste of time and resources.

Now, the tools build the graph based
on the requested services, which
drastically reduces the time needed to
construct the necessary dependency graph.

add servicedir entry at live addon. Add enabled at configuration group entry. Move status entry from path to live addon

This commit sign the end of the "[WIP] allow to switch between trees" works.
The tree directory was used with s6-rc. Tree are now completely handled by
resolve file. That's means that services are not independent of a tree.
Again earn of flexibility.

revamp 66-init. Provide option to only init enabled service or disabled service or all service of a trees

Stop a crash in 66-init when it is used without any arguments.  argc is never 0 so the "if (!argc) " statement won't print the usage.