"delete PRIMARY" -> "delete LHS"
Refactored BNF to be more logical, and disabled features:

* Disabled "for ... of <range>" in favor of "for ... of <array>".
* Disabled else for unless statements.
* Fixed some object name (eg: Expression -> Statement).
Added bin/ast to output the AST.
Updated examples.
Correct unary expressions for +, - and ~.