1.0.10.36: support for Darwin versions that support __DARWIN_UNIX03

1.0.10.36: support for Darwin versions that support __DARWIN_UNIX03

 * on some versions of darwin symbols without a leading _ are dropped
   by the linker. Use a leading _ on Darwin ldso_stub functions.

 * Add a FIXME about 128-bit integeer passing being broken on x86-64

 * _DARWIN_UNIX03 support
   ** os_context_t is now __darwin_ucontext
   ** eip -> __eip (and friends) - use macro hackery EIP etc...
   ** use darwin_ucontext/darwin_mcontext instead of struct
      ucontext/mcontext where appropriate.
   ** struct ucontext -> os_context_t where appropriate

 * allow socket-error for the aceptable errors in inet-socket error
   test cases

 * Add a fix me about a rumored OS bug fix that in name-service tests