Fix 64-bit build on Windows and Visual Studio project files...

SConstruct

Index: SConstruct
===================================================================
--- SConstruct	(revision 3716)
+++ SConstruct	(working copy)
@@ -281,18 +281,12 @@
   },
   'msvc': {
     'all': {
-      'WARNINGFLAGS': ['/WX', '/wd4355', '/wd4800']
+      'WARNINGFLAGS': ['/W3', '/WX', '/wd4355', '/wd4800']
     },
     'library:shared': {
       'CPPDEFINES': ['BUILDING_V8_SHARED'],
       'LIBS': ['winmm', 'ws2_32']
     },
-    'arch:ia32': {
-      'WARNINGFLAGS': ['/W3']
-    },
-    'arch:x64': {
-      'WARNINGFLAGS': ['/W3']
-    },
     'arch:arm': {
       'CPPDEFINES':   ['V8_TARGET_ARCH_ARM'],
       # /wd4996 is to silence the warning about sscanf