Fix Issue 218:  Check for protoc executable in vsprojects directory.

diff --git a/python/setup.py b/python/setup.py
index 8c97439..8188730 100755
--- a/python/setup.py
+++ b/python/setup.py
@@ -20,6 +20,10 @@
   protoc = "../src/protoc"
 elif os.path.exists("../src/protoc.exe"):
   protoc = "../src/protoc.exe"
+elif os.path.exists("../vsprojects/Debug/protoc.exe"):
+  protoc = "../vsprojects/Debug/protoc.exe"
+elif os.path.exists("../vsprojects/Release/protoc.exe"):
+  protoc = "../vsprojects/Release/protoc.exe"
 else:
   protoc = find_executable("protoc")