Added three new very common and useful functions to sandboxUtils

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This is a small change, hopefully not a big deal. I use these three functions a lot and want to build around them, so hoping we can add them in.

They are based on some other functions that Octavio identified then refined. Really useful because between them you can handle a text reference in a submission (submission.nest1.nest2.value) and get the root object (submission), the nested text only (nest1.nest2.value) and just go check if anything is actually there and return in also AND it allows by . sytnax and [] syntax (so submission.nest1[nest2][value] also works!).

No linked issue for this.