TouchArea pressed / released signal.

[ogoffart]

There is already a pressed property, so there can't be a signal with that name.

Or Do we even need such signal if we have an way to run code on property change (#112) then we would just check the pressed changed action.

[jturcotte]

This is going to be one of the main signals of the whole toolkit, so either way I think that it should be as convenient as it can be to use it.

[ogoffart]

there is a pointer-event callback