Increasing compiler version to C++17

As development packages are getting updated with latest features requiring newer versions of C++, we had to make a choice. We can either stuck with the old packages or start using new releases. After some investigation of newer C++ standards and its incompatibilities a decision has been made to increase the overall C++ version of USBGuard from C++11 to C++17. What does this mean for you? From now on, you will require a compiler that supports C++17 to be able to compile USBGuard sources. However, USBGuard will continue to work with old dependencies but will also support the newest development packages. An example of such package is PEGTL of version 3 which uses C++17.