Rcsp cleanup

[andreacassioli]

In this PR I introduce a breaking change to the RCSP algorithm interface along several modernization of the code

Breaking change:

• the RCSP interface does NOT require an edge map (it never had) and thus it should not be required. Thus I remove it all along.

Other changes:

• the edge feasibility flag is moved to be local in to the extension function evaluation
• when accessing the final node list at destination, use a reference instead of a copy
• when a single solution is asked for, move it instead of copy.
• removed macro selecting the allocator deponding on C++ version is obsolete because it tests C++11 which is not supported.

Modernization

• the code is simplified by using auto extensively, that allows fewer type definitions and less verbose code
• some typedef has been rewritten with using
• use std::tie instead of boost::tie