Upgrade conserver8 to version 8.2.4.

Pkgsrc changes:
* Adapt to re-location to github
* Fix patching of the conserver.cf man page
* Adapt to README -> README.md change
* Enable LICENSE setting (even though there's more to it, see comment)

Upstream changes:

version 8.2.4 (March 26, 2019):
  - Correct man page typo (Ed Maste <emaste@freebsd.org>)
  - Remove autotools generated files from repo and create with release
  - Better integration of Cirrus CI - FreeBSD, Linux, and MacOS
  - Moving README to markdown
  - Fix #12 - Remote infomation flags (i.e. "-x") cannot be filtered by console
  - Fix #8 - defaultaccess appears broken
  - Rename configure.in and use autoreconf
  - Better use of version.h and letting configure build things with versions

version 8.2.3 (March 17, 2019):
  - Correct 'impi' typo (Ed Maste <emaste@freebsd.org>)
  - Correct argument type passed to time() (Ed Maste <emaste@freebsd.org>)
  - Fix compilation without deprecated OpenSSL APIs
    (Rosen Penev <rosenp@gmail.com>)
  - Fix compilation without deprecated OpenSSL 1.1 APIs
    (Rosen Penev <rosenp@gmail.com>)
  - Fix #6 - clang "-Wstring-plus-int" warning
    (Bryan Stansell <bryan@conserver.com>)
  - configure.in: Add test for closefrom (Ed Maste <emaste@freebsd.org>)
  - regenerate autoconf files (Ed Maste <emaste@freebsd.org>)
  - Use closefrom if available (Ed Maste <emaste@freebsd.org>)
  - Correct typo (Ed Maste <emaste@freebsd.org>)
  - Add Cirrus-CI FreeBSD CI build config (Ed Maste <emaste@freebsd.org>)
  - off by one found by Ed Maste (Bryan Stansell <bryan@conserver.com>)

version 8.2.2 (May 28, 2018):
  - fixes for OpenSSL 1.1+ - patch by Eneas U de Queiroz
    <cote2004-github@yahoo.com>
  - adjustments to documentation after move to github
  - removal of old RCS/CVS tags since we have git

(he)