Improve Dataset Entry to add system tag for back-and-forth conversations

[CloseChoice]

Add system tag for each answer in a back and forth conversation. So we have to convert [Q1, A1, Q2, A2] to <prompter>q1<eos><system>attrib1<eos><assistant>a1<eos><prompter>q2<eos><system>attrib2<eos><assistant>a2<eos>

This also includes changing the prompter and system order