"Modern" version of the Linux compilation

This branch contains a full adaptation for the Linux compilation. No changes in the behavior of the servo were added, but a new subroutine was included in order to get access to the state of the servo externally. The branch includes user-oriented documentation and a set of makefiles to facilitate the compilation.

I suggest to consider the merge requests !1/!2/!4 first*, since some of the modifications of the present branch were already proposed by @mimc. Please note that in the aforementioned issues there are modifications of the servo under particular conditions, contrary to the present merge request.

After this merge, I propose that the changes are ported to the "non deprecated" repository. Maybe Issue !5 can also be merged before that, so the repository is "merge request" free.

*: I propose to tackle all these together and get rid of them, since they have many points in common ...