+New features:
+ - Non-linear resource sharing: allows to dynamically change the resource
+ capacity. Users can change this capacity by setting a callback which will
+ be called when SimGrid is sharing the resource between the active
+ activities. An activity can be a task running, a read/write IO operation or a
+ communication flow.
+ - Callback signature: double (double capacity, int n_activities): given the
+ current resource's capacity and number of activities running on it,
+ returns the new capacity.
+ - Note that this callback is in the critical path of the system solve and
+ should not take long to execute.
+ - Examples:
+ - Disk: examples/cpp/io-degradation
+ - Link: examples/cpp/network-nonlinear
+ - CPU: examples/cpp/exec-cpu-nonlinear