Easier interface

Hi,

I added a couple of things you may want to have a look:

- specify TextAppearance to the text of the tooltip
- ability to show tooltips without the need of including a TooltipRelativeLayout in the layout, similar way as you show Toasts. 

I incidentally formatted the original code. If you are interested in the changes but don't want the format, let me know and I'll apply the changes again without formatting.

thx