Updated to v1.3.4

**Update:** Upon popular request, I have added a new feature such that
Fluidbox does not enlarge excessively images that lack the necessary
resolution to fill the viewport. Also updated readme to clarify basic
usage details.

**Bug fix:** Fluidbox not working with elements that are hidden. Now
Fluidbox *only binds to visible elements on the page*. If you are
revealing images later (by user interaction, AJAX requests and the
likes), please bind `.fluidbox()` to newly visible elements.