fix tuto-03-animated-triangle.md

[GraydenH]

Sorry, maybe i was not clear in my last PR. My changes were not working yet.

[GraydenH]

I got the first example working but I was not able to figure out how to pass t to the vertex shader.

[est31]

Can you keep this in sync with https://github.com/glium/glium/blob/master/examples/tutorial-03.rs ?

[est31]

Also, #1933 does not need a revert. All the PR changed was to replace poll_events with run. poll_events is gone, as is the top level glutin::Event. So that PR was an improvement of the situation, which is why I merged it. Further improvements might be needed. For that, one should orient oneself on tutorial-03.rs to keep the two in sync.

Can you remove the "revert" from the title and maybe align the inline sources in the md file with tutorial-03.rs? After that, a squash would be useful.

[GraydenH]

I see, The .rs was working but the .md was out of date. I fixed the .md to align with the source code example in a fitting way.

[est31]

@GraydenH thanks, is this ready for review?

[GraydenH]

yeah, good to go @est31

[est31]

Thanks!