build own implementation of Windows system library routines needed for typical clients

_From [bruen...@google.com](https://code.google.com/u/109494838902877177630/) on January 22, 2013 16:55:00_

split from issue #916 .

this issue covers building our own implementation using the DR API and DR's internal syscall infrastructure, rather than building on the native API. while the latter would enable libraries that could be used for other projects, the internal allocs inside ntdll routines mean we need to redirect them and in some cases it's easier to redirect the higher-up kernel32 routine instead.

the initial goal would be to cover the 210 kernel32 routines used by the union of dbghelp, typical C++ clients, and msvcrt.

_Original issue: http://code.google.com/p/dynamorio/issues/detail?id=1063_