* mutate_exists for StorageValue with ValueQuery Signed-off-by: muraca <mmuraca247@gmail.com> * added `#[crate::storage_alias]` to tests Signed-off-by: muraca <mmuraca247@gmail.com> * added StorageEntryMetadata Signed-off-by: muraca <mmuraca247@gmail.com> * Update frame/support/src/lib.rs --------- Signed-off-by: muraca <mmuraca247@gmail.com> Co-authored-by: Oliver Tale-Yazdi <oliver.tale-yazdi@parity.io>