BinaryString now implements interface Comparable.

BinaryString class now implements interface Comparable. The object with
larger BitStream value (numerically) is bigger.

Type: New Feature
Refactoring + bug fix + Test additions.

- Rectoring done throughout the project.
- Removed tab characters with spaces + removed dangling newline characters.
- Bug fix: == operator was being using to perform deep comparison of
  2 objects; replaced with equals method.
- Test additions to TruthTableTest.java.
Added a new interface "DeepClonable".

- Added a new interface "DeepClonable" for performing deep clone actions.
Project restructuring
Added the logixengine.operator package.

- Created a new package that handles all the operator realated logic.
- The enum AllowedOperators is used for declaring all the valid operators.
  All other classes shall refer to this enum when needing any operator
  related data.
- The abstract class Operator wraps around AllowedOperators objects.
  This class is used for performing all the operator specific operations.
  The wrapping ensures that arbitrary operators are not defined, and only
  those declared in AllowedOperators are created.

Type: New Feature