[FEATURE REQUEST] increase file.tidied flexibility with regard to age and size

[nicholasmhughes]

Describe the solution you'd like
The current decision logic only allows an "OR" between age and size. You cannot configure "AND" logic so both age and size limit breaches are required to trigger removal. Additionally, age and size cannot be matched independently with setting the other parameter to a very large value. For instance, you can have age-only removal if you set size to something large you wouldn't see on your system... like 999T

Describe alternatives you've considered
Workarounds usually consist of "shelling out" to cmd.run and a find command with the -delete switch...

Please Note
If this feature request would be considered a substantial change or addition, this should go through a SEP process here https://github.com/saltstack/salt-enhancement-proposals, instead of a feature request.