Web editor adds carriage return to all lines

Observed with omnibus-gitlab 6.8.1-omnibus.4-1 on both Ubuntu 12.04 and CentOS 6.5.

Steps to reproduce:

• create a new project and import https://github.com/randx/six.git
• edit the LICENSE file through the web UI, adding a single line
• view the commit in GitLab

Result: 'Showing 1 changed file with 21 additions and 19 deletions'

Expected: 'Showing 1 changed file with 3 additions and 1 deletions'

This seems to be a regression to https://github.com/gitlabhq/gitlabhq/issues/3982 . The solution elected in that issue is to use the core.autocrlf=input setting of Git. Omnibus-gitlab already does this so we may need a different solution this time around.