Initial docs for RequestHandler.
Initial docs for RequestHandler.

YuanPeir-Chen/turbo-support-mipsel,luastoned/turbo,luastoned/turbo,ddysher/turbo,zcsteele/turbo,ddysher/turbo,YuanPeir-Chen/turbo-support-mipsel,kernelsauce/turbo,mniestroj/turbo,zcsteele/turbo