Improve inactive fund tracking (#6471)

* Improve inactive fund tracking

* Docs

* Introduce the re-migration code

* Bump

* Update runtime/kusama/src/lib.rs

Co-authored-by: Oliver Tale-Yazdi <[email protected]>

* Update runtime/common/src/crowdloan/migration.rs

Co-authored-by: Oliver Tale-Yazdi <[email protected]>

* Update runtime/common/src/crowdloan/migration.rs

Co-authored-by: Oliver Tale-Yazdi <[email protected]>

* Grumbles

* Apply comments suggestions from code review

Co-authored-by: Bastian Köcher <[email protected]>

Co-authored-by: Oliver Tale-Yazdi <[email protected]>
Co-authored-by: muharem <[email protected]>
Co-authored-by: Bastian Köcher <[email protected]>
Co-authored-by: parity-processbot <>