Cache should not be regenerated on PhotoSize change that only changed "increment_count"

[tbabej]

When you save a PhotoSize, the whole photo cache gets regenerated. While this makes sense for changes in other attributes, such as width or watermarks, photo cache should not be regenared if you only switched off/on the increment_count.

I propose that we extend PhotoSize model so that it knows what attributes were changed (as suggested here http://stackoverflow.com/a/13842223 ) and then regenarate the cache only if necessary.

I can submit a pull request if you approve.

[richardbarran]

That would make sense and improve performance - pull requests welcome.