Import Debian changes 20190729-0.1

hol-light (20190729-0.1) unstable; urgency=medium

  * Non-maintainer upload
  * New upstream snapshot (Closes: #876533)
    - Patch for new ocaml and camlp5
    - tweak rules file to stop copy of the new ml file 
      This is already done in upstream build system.
    - do not install .pc file in the system (Closes: #878615)
  * Update copyright file
  * Update copyright file http in https mode