add custom class on overlay trough "data-css"

add custom class on overlay trough "data-css" on trigger + min code
bower.json update
Merge branch 'master' into pr/14

Conflicts:
	venobox/venobox.min.js
version 1.4

update: press Escape key to close
update: return focus when modal is closed
fix: hidden arrows when infinigall is true but without data-gall
attributes
fix: min-height bug on navigation between images
update
Merge branch 'pr/14'