First pass for rewriting the build system

* Refactored all CMake files
* Started working on compiling shaders to header files in CMake

Signed-off-by: Fabian Sauter <sauter.fabian@mailbox.org>

examples/android/android-simple/app/build.gradle

@@ -20,7 +20,6 @@ android {
                         '-DKOMPUTE_OPT_ANDROID_BUILD=1',
                         '-DKOMPUTE_OPT_INSTALL=0',
                         '-DKOMPUTE_OPT_ENABLE_SPDLOG=0',
-                        '-DKOMPUTE_OPT_BUILD_SINGLE_HEADER=0',
                         '-DKOMPUTE_OPT_DISABLE_VK_DEBUG_LAYERS=1',
                         '-DKOMPUTE_EXTRA_CXX_FLAGS=-DKOMPUTE_VK_API_MINOR_VERSION=0'
             }