SOme ground work to support Windows for benchmark farm

Mainly straightforward changes, the only tricky part: detect number of CPU
sockets. Didn't figure out yet how to do this on Windows.

benchmark/foundation/buildbot.py

@@ -49,6 +49,11 @@ def _getBuildbotPlatformRegex(platform, bitness):
             return re.compile(".*linux-glibc[0-9]+-x86_64.*")
         elif bitness.startswith("32"):
             return re.compile(".*linux-glibc[0-9]+-i686.*")
+    elif platform_lower in ("win32"):
+        if bitness.startswith("64"):
+            return re.compile(".*win64.*")
+        elif bitness.startswith("32"):
+            return re.compile(".*win32.*")
     else:
         # TOGO(sergey): Needs implementation
         pass