Added special Error Type
Extended AST classes for the Interpreter pattern (typechecking)
Moved Binary and Unary classes to expression package
Renamed Binary and Unary expression classes to BinaryExpr and UnaryExpr
Added sub (super)classes for binary numeric & bool expressions
Refactored expressions to extend binary super class based on type
Moved binary expressions to subpackages based on expression type
Added missing Unit Test cases for expressions
Fixed bug in ANTLR Grammer => divide matches <= instead of /
Added Unit Tests for unary expressions (needed?)
Refactored all Expression Unit Tests into seperate Unit Test classes
Refactored ast type value to subpackage literal expressions