Linebreaks & Linebreaksbr filters added

https://docs.djangoproject.com/en/dev/ref/templates/builtins/

linebreaks: Replaces line breaks in plain text with appropriate HTML; a
single newline becomes an HTML line break (<br />) and a new line
followed by a blank line becomes a paragraph break (</p>).

linebreaksbr: Converts all newlines in a piece of plain text to HTML
line breaks (<br />).