Add documentation for TOC files
Add documentation for TOC files

superyyrrzz/docfx,LordZoltan/docfx,DuncanmaMSFT/docfx,sergey-vershinin/docfx,dotnet/docfx,928PJY/docfx,sergey-vershinin/docfx,pascalberger/docfx,DuncanmaMSFT/docfx,superyyrrzz/docfx,hellosnow/docfx,pascalberger/docfx,928PJY/docfx,superyyrrzz/docfx,hellosnow/docfx,dotnet/docfx,hellosnow/docfx,LordZoltan/docfx,928PJY/docfx,LordZoltan/docfx,LordZoltan/docfx,sergey-vershinin/docfx,pascalberger/docfx,dotnet/docfx