Add simple for loop for repeating a block

[pipe01]

For example:

{{repeat i := 1 to 6}}
   ...
{{end}}

[sauerbraten]

Jet v4 has a built-in ints-Ranger and new one-var range assignment syntax, so you can write range i := ints(0,6) now to get i == 0 to i == 5.

I think that's enough and there's no need to add new syntax for this use case.

[pipe01]

Yeah that covers it, now I just have to wait for Iris to update to v4. Thank you!