[TTree][NFC] Use \parblock to format multiple-paragraph descriptions
[TTree][NFC] Use \parblock to format multiple-paragraph descriptions

olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root,olifre/root