timeline css: Fix bad color value

[ferdnyc]

This has been bugging me for a while — one of the CSS colors in the .transition styling has a missing hex digit. Fortunately CSS is forgiving enough that it doesn't break the world if we write:

.transition { background-color: #0192c; }

...but it's still a bad value.

It works just fine like this, though:

.transition { background-color: #0192c1; }

[ferdnyc]

Ah, yes, now that cx_Freeze is back down to a compatible version and Travis is unfucked, I can merge this 1-character change.