fixes #276, path manipulation issues on windows. Also fixes server mode

tool/patch_sdk.dart

Index: tool/patch_sdk.dart
diff --git a/tool/patch_sdk.dart b/tool/patch_sdk.dart
index 62c8f5a1603f9f997fead227079948cfa4c8b7f0..276d5fd53e94a4a91914298fcacbe83f8cff3262 100755
--- a/tool/patch_sdk.dart
+++ b/tool/patch_sdk.dart
@@ -15,8 +15,8 @@ import 'package:path/path.dart' as path;
 
 void main(List<String> argv) {
   if (argv.length < 2) {
-    var self = path.relative(Platform.script.path);
-    var toolDir = path.relative(path.dirname(Platform.script.path));
+    var self = path.relative(path.fromUri(Platform.script));
+    var toolDir = path.relative(path.dirname(path.fromUri(Platform.script)));
 
     var inputExample = path.join(toolDir, 'input_sdk');
     var outExample = path.relative(