[1.7.x] Added formatting and line wrapping to checks reference doc.
[1.7.x] Added formatting and line wrapping to checks reference doc.

Backport of 5472bf4df0 from master

jyotsna1820/django,oscaro/django,oscaro/django,jyotsna1820/django,jyotsna1820/django,jyotsna1820/django,oscaro/django,oscaro/django