Changes applied:
* Moved utility files to /util/.
* Removed unused #includes.
* Removed unused ::ffmpeg::tools function.
* Removed unused variables.
* Fixed missing parentheses in the version macro.
* Fixed missing override on virtual function overrides and removed unnecessary virtual keyword from them.
* Disabled additional warning for ATL headers on MSVC only.
* Replaced direct printf parameters with their macro equivalent.
* Replaced C-style casts with C++-style casts.
* Applied clang-format again after an earlier change to the CMake file broke the integration for it.
With this, GCC 8 and above should now be able to compile the project both in obs-studio and as a standalone install. Some features are currently still not fully supported and require extra work, but the majority of things are supported and work out of the box. Exact feature parity can be looked up here on the wiki: https://github.com/Xaymar/obs-StreamFX/wiki/Platform-Feature-Parity
Related: #119#98#30
