Changes to List accounts

the query request parameter account_type was restricted to a list of enum values

added the new enum value available to the query request parameter account_type

added the new enum value collateral to the query request parameter account_type

added the new enum value collateral_deficiency to the query request parameter account_type

added the new enum value payable to the query request parameter account_type

added the new enum value receivable to the query request parameter account_type

added the new enum value staked to the query request parameter account_type