I love that detail and considering that it was likely the whole point of that room, I don't consider it just an egg for the nerds. It's probably a) part of an over-arc for the series as a whole and part of a lead in for the Avengers movie franchise, likely for a phase 3 movie.
That would be my guess. I thought phase 2 is leading to Thanos and then after that will be a build to the Skrulls* invasion.
*My Marvel knowledge does not extend into Thanos' parentage or origins. Before finishing this poste I had to engoogle to see if Thanos was an actual Skrull. I only read enough on the wiki to see that his momma was a Skrull** and that's it.
**Your mom is so Skrull, she thought something something pertinent and humorous relating to Marvel and or over-all comics mythology that only nerds would understand.