[pgjdbc/pgjdbc] dc3c55: packaging: update Fedora's CI

  Branch: refs/heads/fedora-ci-update
  Home:   https://github.com/pgjdbc/pgjdbc
  Commit: dc3c55f91220557cd9a4f526bf31c48c28f481f2
      https://github.com/pgjdbc/pgjdbc/commit/dc3c55f91220557cd9a4f526bf31c48c28f481f2
  Author: Pavel Raiskup 
  Date:   2018-01-19 (Fri, 19 Jan 2018)

  Changed paths:
    M .travis/travis_build.sh
    M packaging/rpm/.srpmconfig
    R packaging/rpm/.srpmgen
    M packaging/rpm/fedora-image/Dockerfile
    M packaging/rpm/fedora-image/copr-ci-git
    M packaging/rpm/postgresql-jdbc.spec.tpl
    M packaging/rpm_ci

  Log Message:
  -----------
  packaging: update Fedora's CI

* Update Dockerfile to Fedora 27
* spec template synced with Fedora Rawhide