Fullscreen improvement

[adaniello]

A simple optimization (in my opinion): i removed anchor tag from fullscreen button definition and event listeners.

In this commit i want to:

1. avoid nested anchors (see example in http://alfredobarron.github.io/smoke/#/fullscreen);
2. have a cleaner code that works fine in all circumstances (have you tried to place it in a navbar?);
3. feel free to use my html code for button;
4. support also multiple button fullscreen in the same page;
5. optimize code removing event listener.

A working example at http://codepen.io/anon/pen/gpZRar

[alfredobarron]

1 Nested anchors i use for the example
2 Yes i use in a navbar and insert the anchor into a div
5 The listeners are for keyboard event scape.

[adaniello]

@alfredobarron ok for listeners, now i understand. I'll add the listners.

About the "lite" code/template (removing anchor tag), i think that this is better because user is free to use his code for button: user can choose about style, position, parent with fewer restrictions.
And then, when i tell you about navbar, i tell about a list item in bootstrap style.
What do you think about? Can we try a new way or not?
Thanks

P.S.: please, update example in doc removing anchor :-)