Added extra_class to filer_image.

[jrutila]

One can add extra string for the image that will be appended to the class-tag.

This is useful for example if one would need to add like img-responsive class to images when using wrapbootstrap templates.

[stefanfoulis]

Wouldn't you want all images site wide to be responsive (so you'd override the image template and hardcode the change)?

That being said, we introduced a configurable "style" on most plugins, which can be used to render with selectable templates.

[jrutila]

I think in some cases it depends on what page and slot the image is in. So maybe it should be also 'certain placeholder in certain template' -wide. So one should be able to override the image template for certain templates placeholder. Would this sound any good? Where can it be configured then?

[stefanfoulis]

For the "certain placeholder" case you could wrap the whole placeholder in a div with a class and use that for styling.