There seem to be two different versions of mscorlib.txt in the repo: [src/mscorlib/mscorlib.txt](https://github.com/dotnet/coreclr/blob/master/src/mscorlib/mscorlib.txt) and [src/mscorlib/src/mscorlib.txt](https://github.com/dotnet/coreclr/blob/master/src/mscorlib/src/mscorlib.txt). Is there any reason for that?