Add support for disabling feature datasets (#6666)

This change adds support for disabling datasets, such that specific
files are not loaded into memory when running OSRM. This enables users
to not pay the memory cost for features they do not intend to use.

Initially, there are two options:
- ROUTE_GEOMETRY, for disabling overview, steps, annotations and waypoints.
- ROUTE_STEPS, for disabling steps only.

Attempts to query features for which the datasets are disabled will
lead to a DisabledDatasetException being returned.

src/util/exception.cpp

@@ -1,5 +1,7 @@
 #include "util/exception.hpp"
 
+#include <utility>
+
 // This function exists to 'anchor' the class, and stop the compiler from
 // copying vtable and RTTI info into every object file that includes
 // this header. (Caught by -Wweak-vtables under Clang.)
@@ -16,4 +18,5 @@ namespace osrm::util
 
 void exception::anchor() const {}
 void RuntimeError::anchor() const {}
+void DisabledDatasetException::anchor() const {}
 } // namespace osrm::util