What it does
When rendering animations, blender currently shows the time consumed to render the current frame and the last frames render time.
This patch shows the total render time for animation renders.

Why it is useful
This allows the user to have a much more educated guess on total render time, especially when the time used for a single frame is tiny:
I had a real-world case where times jumped between 00:00:00 and 00:00:01 per frame - this was absolutely correct, but not very useful for calculating an estimate for the whole animation.

How it works
It introduces an additional timestamp called starttime_animation. This is set to zero by default.
If a animation render is started with RE_RenderAnim() the timestamp from the current (=first) frame is copied to it.

In the display-code, this is used to detect whether to show it (starttime_animation != 0.0 -> animation) or not (starttime_animation == 0.0 -> single frame).

Question

• The patch introduces a new translatable string TIP_("| Anim:%s "). How is that handled in regard to notifying the translation-team?