Merge PR #3243: allow multiple simultaneous redelegations/ubds between same delegator/validator(s) addresses

* remove kv seperation for marshalling

* pending

* cleanup

* cleanup x2

* pending

* working

* minor refactors

* entry structs defined

* uncompiled mechanism written

* add many compile fixes

* code compiles

* fix test compile errors

* test cover passes

* ...

* multiple entries fix

* ...

* more design fix

* working

* fix test cover bug

* Update PENDING.md

* update comment around queue completion for redelegations/ubds

* basic spec updates

* remove ErrConflictingRedelegation

* @cwgoes comments are resolved

* Update x/staking/keeper/slash.go

Co-Authored-By: rigelrozanski <rigel.rozanski@gmail.com>

* address @alexanderbez comments

x/staking/simulation/invariants.go

@@ -59,7 +59,9 @@ func SupplyInvariants(ck bank.Keeper, k staking.Keeper,
 			return false
 		})
 		k.IterateUnbondingDelegations(ctx, func(_ int64, ubd staking.UnbondingDelegation) bool {
-			loose = loose.Add(sdk.NewDecFromInt(ubd.Balance.Amount))
+			for _, entry := range ubd.Entries {
+				loose = loose.Add(sdk.NewDecFromInt(entry.Balance.Amount))
+			}
 			return false
 		})
 		k.IterateValidators(ctx, func(_ int64, validator sdk.Validator) bool {