Improve boolean handling

In library there is this code:

   def set_ignore_implicit_angular_wait(self, ignore):
        if not is_boolean(ignore):
            raise TypeError("Ignore must be

But it might be better to use Robot Framework or SeleniumLibrary is_truthy method to improve boolean handling. SeleniumLibrary method is in here: https://github.com/robotframework/SeleniumLibrary/blob/master/src/SeleniumLibrary/utils/types.py
And it has been there since 3.0 release.

SeleniumLibrary boolean handling is explained in here: http://robotframework.org/SeleniumLibrary/SeleniumLibrary.html#Boolean%20arguments

I can provide you a pull request to fix the problem. Should I copy paste the implementation or can I use method from the SeleniumLibrary? If I can, it will raise minimum required SeleniumLibrary to 3.0.

Inizia con il metodo set_ignore_implicit_angular_wait mostrato nell’issue, quindi leggi types.py di SeleniumLibrary e la relativa documentazione sugli argomenti booleani. Conferma i valori booleani supportati e se il progetto può usare SeleniumLibrary 3.0; il lavoro è completato quando questa impostazione accetta le forme booleane previste e rifiuta in modo coerente i valori non validi.