Remove sample loader from the code

[Agustin Alba Chicar]

Remove the sample loader from the code and create a new branch to hold them until we get the RNDF implementation approved in Drake.

[Agustin Alba Chicar]

Branch --> test/Sample_Loader has the code to load the samples with RNDF code. Current working branch --> Issue/RNDF_Maliput_Implementation has only the RNDF implementation.

Also, I removed some other changes in code that were not appropiate for the PR.