Docu: Clarify usage of LONG_PRESS in system.button channel

[rbi]

This this documentation states that a system.button channel has only the events "SHORT_PRESSED, DOUBLE_PRESSED and LONG_PRESSED". A LONG_PRESSED event is only useful if you know when it ends. How do you know? Please clarify that in the documentation.

My guess is that the channel should contain the string "LONG_PRESSED" as long as the press lasts and is cleared afterwards. The Homatic binding seams to interpret it that way. Is that the correct interpretation?

"Trigger channel" sounds like something that only receives trigger events and has no state or the state is irrelevant. In that case you would expect the system.button channel to have an event LONG_PRESS_RELEASED.