api: speed: remove unused AccessTokens

[syndr0m]

select count(*) from "AccessTokens" where created < '2017/01/11 00:00:00'
-- 619319

create table "backupAccessTokens20170112" as table "AccessTokens";
delete from "AccessTokens" where created < '2017/01/11 00:00:00';
select count(*) from "AccessTokens";
-- 5695

[syndr0m]

select count(*) from "RefreshTokens" where created < '2016/12/10 00:00:00'
-- 1149966

create table "backupRefreshTokens20170112" as table "RefreshTokens";
delete from "RefreshTokens" where created < '2016/12/10 00:00:00';
-- Query returned successfully: 1149966 rows affected, 5.6 secs execution time.
select count(*) from "RefreshTokens";
-- 152550