Fixed naming.
Added NetBeans IDE integration.
Added class skeleton for class `Ball`.
Added basic `Ball` implementation.
Added basic movement for the `Ball`.
Fixed names of static constants.
Introduced structure for x and y coordinates.
Added comments.
Introduced structures for insets and dimension.
Added collision detection for the `Ball`.
Refactored structured to classes.

This is a more modern approach. OOP should always use accessors. This
also ensures that the objects are immutable.
Updated files.
Fixed order of parameters for Insets constructor.
Added `Paddle` class.