slapos_accounting: Add legacy Aggregate trade condition

    For the time, Taxes were 19.6% on quite old systems.
5 jobs for master in 0 seconds
Status Job ID Name Coverage
  External
passed SlapOS-Master.UnitTest-Master

01:08:06

passed SlapOS.Eggs.UnitTest-Master.Python2

00:13:38

passed SlapOS.Eggs.UnitTest-Master.Python3

00:27:31

passed SlapOS.Eggs.UnitTest-Master.Python2

00:10:04

passed SlapOS.Eggs.UnitTest-Master.Python3

00:09:48