Problem was that when running stow_contents/unstow_contents recursively from
stow_node/unstow_node the information for the source path (without the dot- to
. transformation) was lost.

In the case of stow_contents the solution is just to remove the leading
dots (..) from the $source path (since the $source path is passed as an argument
to the function)

In the case of unstow_contents the solution is the same as for stow_contents but
the arguments was now passed so I added it to the function.

This variables is used to keep track of the current level in the source.