Replaced uint64_t with size_t in the places that make sense and
added spv_const_binary{,_t} to allow the interface to accept non
modifiable spirv where appropriate.
Note that we are more strict than Google style for one aspect:
pointer/reference indicators are adjacent to their types, not
their variables.
find . -name "*.h" -exec clang-format -i {} \;
find . -name "*.cpp" -exec clang-format -i {} \;