Generate the well-known types in C#

This involves:
- Specifying a namespace in each proto (including ones we'd previously missed)
- Updating the generation script
- Changing codegen to implement IReflectedMessage.Fields explicitly (a good thing anyway)
- Changing reflection tests to take account of the explicit interface implementation

Non-generated code in this commit; generated code to follow

1 files changed, 1 insertions, 1 deletions

diff --git a/src/google/protobuf/compiler/csharp/csharp_message.cc b/src/google/protobuf/compiler/csharp/csharp_message.cc
index 7cbba911..4acc899b 100644
--- a/src/google/protobuf/compiler/csharp/csharp_message.cc
+++ b/src/google/protobuf/compiler/csharp/csharp_message.cc
@@ -215,7 +215,7 @@ void MessageGenerator::Generate(io::Printer* printer) {
     "  get { return $descriptor_accessor$; }\n"
     "}\n"
     "\n"
-    "public pbr::FieldAccessorTable Fields {\n"
+    "pbr::FieldAccessorTable pb::IReflectedMessage.Fields {\n"
     "  get { return $umbrella_class_name$.internal__$identifier$__FieldAccessorTable; }\n"
     "}\n"
     "\n"