- winbase.h: Make winbase.h usable by MSVC
- winuser.h: Add missing const specifiers to GetTabbedTextExtentA/W, TabbedTextOutA/W, ToAscii/Ex and ToUnicode/Ex
- Make gdi32, user32, beepmidi and csrss drmk build in msvc
- Fix most msvc issues in win32k -- a few remain
- Make ntoskrnl compile with /W1 again
svn path=/trunk/; revision=42314