Feature Request: Add Free Planets to Slots

[aixtools]

I know it isn't like the other slots that are job and skill based - BUT - since it is skilled based having the number of 'free planets' to control of PI, imho, would be a great addition.

And, I hope, not too difficult to add.

[GoldenGnu]

Maximum number of planets are dependent on the skill: https://wiki.eveuniversity.org/Skills:Planet_Management#Interplanetary_Consolidation

Current number of planets are just:
characters/{character_id}/planets/

It looks easy enough to implement