* Added scrolling text functionality.  AKA when text is too long to be fully displayed in a textbox, it will scroll
  with the caret.
* The functionality is implemented in the Text and DefaultTextGraphics classes.
* In order to use this functionality, added another UIImplementer: TextScroller.
* TextScroller should be used by a Caret object, and implementets only one method, which is onSetLocation.
* Plan to implement a NullTextScroller(TextScroller) class which will simply override the onSetLocation method
  to do nothing, in case you don't want scrolling functionality.
* Textboxes now support arbitrarily long strings, but like any other textbox, they will start to see slowdowns with
  very long strings due to hardware limitations.
* Plan to implement a length limit for text objects which would stop accepting input once the length limit is reached.