TrimHandler: don't try to encode dummy videos.
Aegisub-Motion: fix first-run trim config popup.

I'm certain this used to work and I'm really not sure what changed.
TrimHandler: use path specifier for temp directory.
LineCollection: set useful data with addLine.
Aegisub-Motion: move createPrefix checkbox next to prefix.
Docs: update submodule.
Aegisub-Motion: fix trim config popup for real.

I don't know how I keep screwing this up. It is spectacular.
Version bump.