Create new `AccountItems` and `AccountItemClassifications` tables
Insert initial datas into `AccountItemClassifications`
Insert initial account items into `AccountItems` table
Set all of `Accounts.itemId`
Save `itemId` column on `Account#save`
Join `AccountItems` table to find item name on `Transaction#find`
Join `AccountItems` table to find item name on `TotalAccounts#select`
Stop saving `Accounts.item`
Merge branch 'enhancement/extract-new-tables'