lib/richPp: Fix a bug related to the compatibility with ocaml 3.12   - The previous version of this module was using a feature of     the Format module of ocaml 4.01.
lib/richPp: Fix a bug related to the compatibility with ocaml 3.12
  - The previous version of this module was using a feature of
    the Format module of ocaml 4.01.

  - Add comments.

asr/coq,barras/coq,letouzey/coq-wip,ppedrot/coq,8l/coq,silene/coq,aspiwack/coq,asr/coq,letouzey/coq-wip,TheTypoMaster/coq,Zimmi48/coq,TheTypoMaster/coq,letouzey/coq-wip,ale-f/coq,pirapira/coq2rust,gmalecha/coq,Ptival/coq,mlasson/coq,barras/coq,amintimany/coq,gares/coq,aspiwack/coq,Matafou/coq,mattam82/coq,Matafou/coq,ppedrot/coq,maximedenes/coq,Lionel-Rieg/coq,Ptival/coq,maximedenes/coq,silene/coq,TOSPIO/coq,silene/coq,ejgallego/coq,gares/coq,ale-f/coq,TOSPIO/coq,shindere/coq,herbelin/github-coq,coq/coq,herbelin/github-coq,Lionel-Rieg/coq,coq/coq,coq/coq,jpdeplaix/coq,jpdeplaix/coq,JasonGross/coq,ppedrot/coq,barras/coq,shindere/coq,jpdeplaix/coq,mlasson/coq,ejgallego/coq,gmalecha/coq,aspiwack/coq,TOSPIO/coq,8l/coq,ppedrot/coq,amintimany/coq,ppedrot/coq,SkySkimmer/coq,TheTypoMaster/coq,william-lawvere/coq,maximedenes/coq,Matafou/coq,mlasson/coq,Lionel-Rieg/coq,SkySkimmer/coq,ejgallego/coq,shindere/coq,pirapira/coq2rust,SkySkimmer/coq,Zimmi48/coq,letouzey/coq-wip,ale-f/coq,mattam82/coq,gmalecha/coq,letouzey/coq-wip,gares/coq,JasonGross/coq,JasonGross/coq,Zimmi48/coq,william-lawvere/coq,8l/coq,herbelin/github-coq,Zimmi48/coq,amintimany/coq,gares/coq,pirapira/coq2rust,mattam82/coq,SkySkimmer/coq,gares/coq,Ptival/coq,asr/coq,ejgallego/coq,JasonGross/coq,william-lawvere/coq,maximedenes/coq,coq/coq,maximedenes/coq