Customizable build scripts

[mctb32]

Add ability for the users of the library to easily customize the diligent build options - provide custom list of build targets and pass custom compiler options.

Fixed in e7501a4

I added a section to the main repo's readme describing how to use custom build configuration file. To have four configurations (Debug, DebugMT, Release, ReleaseMT) you can start with the following BuildConfig.cmake file:

function(custom_configure_build)
    if(CMAKE_CONFIGURATION_TYPES)
        # Debug configurations
        set(DEBUG_CONFIGURATIONS DEBUG DEBUGMT CACHE INTERNAL "" FORCE)
        # Release (optimized) configurations
        set(RELEASE_CONFIGURATIONS RELEASE RELEASEMT CACHE INTERNAL "" FORCE)
        # CMAKE_CONFIGURATION_TYPES variable defines build configurations generated by cmake
        set(CMAKE_CONFIGURATION_TYPES Debug DebugMT Release ReleaseMT CACHE STRING "Configuration types: Debug, DebugMT, Release, ReleaseMT" FORCE)

        set(DEBUG_CPP_FLAGS "/MTd /Od /W4 /wd4100 /wd4505")
        set(DEBUG_C_FLAGS "/MTd /Od /W4 /wd4100 /wd4505")

        set(CMAKE_CXX_FLAGS_DEBUGMT ${DEBUG_CPP_FLAGS} CACHE INTERNAL "" FORCE)
        set(CMAKE_C_FLAGS_DEBUGMT ${DEBUG_C_FLAGS} CACHE INTERNAL "" FORCE)
        set(CMAKE_EXE_LINKER_FLAGS_DEBUGMT "/OPT:REF" CACHE INTERNAL "" FORCE)
        set(CMAKE_SHARED_LINKER_FLAGS_DEBUGMT "/OPT:REF" CACHE INTERNAL "" FORCE)

        set(RELEASE_CPP_FLAGS "/MT /W4 /wd4100 /wd4505 /arch:AVX2 /wd4189 /GR- /GL /GF")
        set(RELEASE_C_FLAGS "/MT /W4 /wd4100 /wd4505 /arch:AVX2 /wd4189 /GR- /GL /GF")

        set(CMAKE_CXX_FLAGS_RELEASEMT ${RELEASE_CPP_FLAGS}  CACHE INTERNAL "" FORCE)
        set(CMAKE_C_FLAGS_RELEASEMT ${RELEASE_C_FLAGS} CACHE INTERNAL "" FORCE)
        set(CMAKE_EXE_LINKER_FLAGS_RELEASEMT "/OPT:REF" CACHE INTERNAL "" FORCE)
        set(CMAKE_SHARED_LINKER_FLAGS_RELEASEMT "/OPT:REF" CACHE INTERNAL "" FORCE)
    endif()
endfunction()

I also fixed build system to properly target 8.1 SDK, so that you can run the following command to generate x86 solution with four configurations defined in the config file:

cmake -D BUILD_CONFIGURATION_FILE=BuildConfig.cmake -D CMAKE_SYSTEM_VERSION=8.1 -H. -B./cmk_build/Win32 -G "Visual Studio 15 2017"