[Clas12_dileptons] JPsi analysis review comments and answers

[pierrec]

Hello All,

I have received the first round of the review of the JPsi analysis last 
week, and started working on the answer as discussed at the meeting 
today.
You can find the document and a draft of the answers here:
https://docs.google.com/document/d/1enURrOq-QkIhUZjyeiTkyn4MlQNwNNUphAHNTESPcuI/edit?usp=sharing

Please feel free to contribute to this document

Best,
Pierre