Based on http://www.reddit.com/r/linux/comments/2bffgt/gitlab_71_released/cj59wvz reword this requirement, thankstictatonifonical.
Note exim problems.
Merge branch 'word-requirement-a-bit-more-realistic' into 'master'

Word requirement a bit more realistic

See commit message

See merge request !155
Add warning about backing up the config.
Merge branch 'backup-settings-warning' into 'master'

Backup settings warning

Fixes #1457

See merge request !992
Explain project services.
Merge branch 'project-services-explained' into 'master'

Project services explained

See merge request !993
Merge branch 'exim-problems' into 'master'

Exim problems

After merge report back to https://github.com/gitlabhq/gitlabhq/issues/4866

See merge request !990
Merge branch 'master' of gitlab.com:gitlab-org/gitlab-ce