Remove ccache from the build utils, since ccache is only effective for compiler
Split variable cmake into cmake_configure and cmake_args for clarity
Use ninja as default generator for cmake to speed up building process
Add CMAKE_BUILD_PARALLEL_LEVEL to control the maximum number of build processes
Call cmake to compile and install, which allows set generator without changing compile and install commands, and making CMAKE_BUILD_PARALLEL_LEVEL take effect automatically
Prefer to use cmake's own way of setting C/C++ standard and linker type if available, this prevents cmake projects from setting the default value for CMAKE_<LANG>_STANDARD and overwriting renpy's C/C++ std version
This PR enhances the cmake build system integration, specifically, it does the following things:
-fuse-ld=llddirectly, this is llvm's recommend method to use lld in https://lld.llvm.org/#using-lldccachefrom the build utils, since ccache is only effective for compilercmakeintocmake_configureandcmake_argsfor clarityninjaas default generator for cmake to speed up building processCMAKE_BUILD_PARALLEL_LEVELto control the maximum number of build processesCMAKE_BUILD_PARALLEL_LEVELtake effect automaticallyCMAKE_<LANG>_STANDARDand overwriting renpy's C/C++ std version