Changelog
* New interpreter. Includes **Scanner**, **Lexer** and **Parser**. See [Interpreter](https://github.com/centaurialpha/pireal/tree/master/src/core/interpreter).
* Now you can work with **dates** and **times** natively.
query_1 := select date > '01/01/1991' (dates);
* Improved GUI with QtQuick Controls.
* Support for the operations of: **Left**, **Right** and **Full Outer Join**.
query_1 := employee louter salary;
query_2 := employee router salary;
query_3 := employee fouter salary;
* Improved data management with **Model/View/Delegate** pattern.