[cleanup] fix some GCC 7 warnings
This fixes some warnings regarding deprecated throw(...)
(see #71 (closed)) and an error due to a missing include for std::function
when using the C++ Standard Library from GCC 7.
This fixes some warnings regarding deprecated throw(...)
(see #71 (closed)) and an error due to a missing include for std::function
when using the C++ Standard Library from GCC 7.