Completely untested so far - easier to get started in VS and then transfer to Linux for tweaking...

Document everything, and turn on errors if we fail to document anything in the future

Fix build warnings around unused variables

Various compilation fixes

JSON formatting for FieldMask

Remove a redundant layer of directory hierarchy.

Allow partially-trusted callers again.

Expose Coded*Stream constructors directly.

Fixes issue #552. (And yay, it looks like our build profile supports this...)

Add ReleaseSigned configuration for C#

Formatting of Struct as JSON

This seems remarkably little code, but it appears to work. I can add tests for invalid structs at some point, once the general approach is approved.

JSON formatting for Timestamp and Duration

This is taking an approach of putting all the logic in JsonFormatter. That's helpful in terms of concealing the details of whether or not to wrap the value in quotes, but it does lack flexibility. I don't *think* we want to allow user-defined formatting of messages, so that much shouldn't be a problem.

Simpify json tests

Fix C# JSON field ordering

Fix build failure on Windows when Unicode build is enabled.

Fix trivial bug in field orderings.

Use ' instead of " in the expected JSON, then replace it before asserting.

(Shows the benefit of unit testing even code "too simple to fail"...)

Well-known type operations for Timestamp and Duration

While I've provided operators, I haven't yet provided the method equivalents. It's not clear to me that
they're actually a good idea, while we're really targeting C# developers who definitely *can* use the user-defined operators.

Handle field names of "descriptor" and "types".

This is a follow up CL for e9abc404,
which breaks build when UNICODE macro is defined.

protoc has explicitly called MBCS version of APIs / funcsions
rather than UTF-16 (wchar_t) version of them regardless of
UNICODE macro definition (and it indeed works as expected).
Hence it makes sense to call GetModuleFileNameA explicitly.

Expose GetUmbrellaClassName in csharp_names.h

Merge C# proto3 from csharp-experimental to master