Add Game.constructionSites to API

[Dissi]

Sometimes when your script bollocks-up you might lose a few construction sites in some rooms. 

I'd would be handy if we can get all construction sites placed by you in a handy game constant to avoid searching all rooms manually.

[tedivm]

This is especially important if access to a room is lost for some reason and you literally can't get visibility to it. At that point if you don't have the ID stored you have no way to get it.

[Vervorris]

This would be so handy.

[artch]

This feature has been introduced in this changelog.

[Primoz56]

how does one use this function? it just returns me [object object], how do i convert this into an array of structures?