[Svn] [roundcube/roundcubemail] 0c8e29: Mention required min. version of lessc (#7031)

[Aleksander Machniak]

  Branch: refs/heads/release-1.4
  Home:   https://github.com/roundcube/roundcubemail
  Commit: 0c8e29fcbfeb79c9525b70175f2a907fe9c1b624
      https://github.com/roundcube/roundcubemail/commit/0c8e29fcbfeb79c9525b70175f2a907fe9c1b624
  Author: Aleksander Machniak <alec at alec.pl>
  Date:   2019-11-13 (Wed, 13 Nov 2019)

  Changed paths:
    M INSTALL
    M UPGRADING
    M skins/elastic/README.md

  Log Message:
  -----------
  Mention required min. version of lessc (#7031)