Replace Clock instance by Timer instance (three r183+)

[vincentfretin]

Replace Clock instance by Timer instance. Clock is deprecated in three r183.
To be merged after the repo is updated to three r183+

I didn't call self.timer.connect(document);
The connect(document) call on the timer leverages the Page Visibility API similar to Clock to prevent large time jumps when the browser tab is inactive.
I don't think we want it?

FYI networked-aframe accessed that clock instance so I did some changes in networked-aframe/networked-aframe#521 That's the only occurrence of it I saw in community components.

[vincentfretin]

Actually I think it's good to have the self.timer.connect(document), it fixes the issue with orbit-controls="autoRotate: true" that speed up the rotation when you come back to the tab. I amended the commit.