Adding two new functions(% and log) in Calculadora.py

[jlozanopenagos]

Adding two new functions(% and log) in Calculadora.py and Calculador.py:

1. Button Creation and Layout:

• Two new buttons, labeled "log" and "%", have been added to the calculator interface.
• These buttons are created with the appropriate text and styling to represent the logarithm and percentage operations.

2. Event Handling:

• Event handlers have been defined for the new buttons to capture user input and perform the corresponding operations.
• The command attribute of the buttons is set to call specific methods when clicked.

3. Expression Processing:

• A new method _process_expression has been implemented to handle the processing of mathematical expressions containing the logarithm and percentage operations.
• Within this method, the presence of the logarithm operation is detected, and if found, the logarithm function is evaluated and replaced with its result in the expression.
• Error handling is included to deal with invalid arguments or operations, ensuring the stability of the calculator.

4. Result Display:

• The method _set_result_in_input has been updated to handle the display of results for expressions containing logarithms and percentages.
• If an error occurs during evaluation, such as an invalid operation or division by zero, the method displays an appropriate error message.

5. User Interface Interaction:

• Users can now input logarithmic expressions by clicking the "log" button, followed by the number or expression inside parentheses. It can be use with others operations
• Similarly, the "%" button allows users to input percentage calculations, which are then processed accordingly.