Option to use bangs instead of MIDI clock as input

[gilbertohasnofb]

First of all, thank you for this abstraction, this is really, really cool. I'm using it to hook my Volca synthesisers and I'm having a blast with it.

As a request, would it be possible to add an option for a metro input, or perhaps alter the input of your [eucgui] object altogether? Using MIDI clock could be good for some applications, but I think that simply being able to connect a [metro] object directly to [eucgui] would be much handier. At the moment, I am adding a [counter] in between them, but I do think this solution might not be the best as the counter will, at some point, reach very high values.