Add a check version function

[thinkerbot]

Heck, maybe this is just something to document.

. ts
assert [ "$ts_version" \> "1.0" ]

Or similar...

[thinkerbot]

Actually, no unfortunately that doesn't work. The exit from the assert will still trigger the tests (which will all fail, at least there is that). And really there should be some check performed, so there can be sensible output.