Right now, the standard allocator is being declared as part of the
"util.h" header as a set of inline functions. As with the crtdbg
allocator functions, these inline functions make it hard to convert to
function pointers for our allocators.

Create a new "stdalloc" module containing our standard allocations
functions to split these out. Convert the existing allocators to macros
which make use of the stdalloc functions.