bugfix: ZeroDivisionError for images with dimensions like 1x54 px
bugfix: ZeroDivisionError for images with dimensions like 1x54 px
Merge branch 'master' of https://github.com/vovkd/sorl-thumbnail into vovkd-master

* 'master' of https://github.com/vovkd/sorl-thumbnail:
  bugfix: ZeroDivisionError for images with dimensions like 1x54 px
  bugfix: ZeroDivisionError for images with dimensions like 1x54 px