Provide for detailed inspection of pregnancies directly from the Incubator pregnancy list

I often find myself looking at the incubator list and then going through facilities to find a slave so I can decide which specific fetus to reserve an incubation tank for, or even just to know whether it's worthwhile to do so, and then coming back to the incubator, ad nauseum.

This MR adds a direct link to the relevant slave's Analyze Pregnancy page (if the pregnancy monitoring system upgrade is installed), so you don't have to find the right slave interact page, and returns you from there to the Incubator if that's how you arrived.

Tested?

I tested slave pregnancy inspection pretty thoroughly (from both active call sites and in a variety of cases), and everything works there. I don't have an appropriate save for PC pregnancy inspection, but it's much simpler (doesn't have to go through any the of AS Dump stuff) so I expect it to work fine.

merged

mentioned in commit 99af75d7