Allow Moving Target Overlay Outside of Image

Currently, the target overlay is constrained inside of the image. In a situation when a target isn't found and needs to be manually positioned, the constraint poses challenges which make it difficult or impossible to get the overlay in the right place.

1. If the target is at the edge of the image, it may be impossible to get it to line up without the overlay going outside the boundary.

2. Rotating the overlay, e.g. 180 degrees, is difficult if you can't ever go outside the boundaries of the image.