[aggConfig] make the id part of state
[aggConfig] read the id from state, pick ids for new states
[discover/segmented_fetch] itterate the agg keys, rather than trying to find them
[aggConfig] test the placement and export of ids
[editor/nestingIndicator] use the id of the item if available
Merge pull request #1931 from spenceralger/dependable-agg-ids

Dependable agg ids