Improve linker performance by either enabling GL and LTGC on certain projects at the same time, enabling it for all projects, or disabling it all together
- Set character set to multi-byte (this is because the game is also build with it).
- Utility function 'FileExists' now takes a raw string pointer, this avoids having to construct a fs::path each time its getting called (which is quite a lot!).
- Performed overall cleanup to code containing logic to override load paths. Mostly removing unnecessary copy constructions.
Previously, it was all controlled from the global init (applied to all projects), but some projects need different options. With these changes, you can disable the common options applied in the 'add_module' macro, and set your own if desired.
Treat them as errors globally. Most of the time a warning is a bug, or problem in code that could be solved in a different (better) manner. Thirdparty code have this disabled. The warnings as errors option can be globally disabled through the CMake GUI, but this is not recommended.
Enable Link Time Code Generation as some libraries are compiled using /GL (Whole Program Optimization) which requires the code generation to be delayed to link time. Not doing this will result in longer build times, as the linker has to terminate its progress if it links a library compiled with /GL, and restart this operation using /LTCG.
Use the 'add_module' macro to add modules without creating duplicate code. This macro also takes a reuse PCH as parameter, so modules that need a precompiled header, could reuse those from different targets that compile them. This commit also restructures the group order of the generated solution files for easier code navigation.
