Fixes #6955: using CSS to mimic a <pre> for multiple line support.

Instead of adding linebreaks to the HTML and binding simply use
white-space: pre; to mimic a pre.  This commit also removes the
linebreak filter and tests.

http://projects.theforeman.org/issues/6955
Merge pull request #4613 from waldenraines/6955

Fixes #6955: using CSS to mimic a <pre> for multiple line support.