+ Forms without ID will receives a genarated hash to be used as hook.
+ The 'stepy-titles' class was renamed to 'stepy-header'.
+ The 'stepy-{id}-titles' ID was renamed to 'stepy-{id || hash}-header'.
Extracted the header builder.
+ The 'step' class was renamed to 'stepy-step'.
+ The '{id}-titles-{index}' was renamed to '{id}-head-{index}'.
+ All callbacks now receives the variable `this` as DOM element instead jQuery.
Extracted the navigator builder.
+ The 'current-step' class was renamed to 'stepy-active'.
Putting the heads on DOM.