JsExpression explanation should be made more language agnostic

[Remi-Gau]

Minor issue

This currently reads as:

https://www.repronim.org/reproschema/schema/#computespecification

A JavaScript expression to compute a score from other variables.

This sort of presumes that only Javascript will be used for computation but I am now doing form validation with a python backend.

So I may end up putting python expression in something that says it should be Javascript. Probably would be a good thing if the schema had a way to capture what programming language is used for the expressions.

Same goes for the isVis where I am now expressing conditionals in python code and not JavaScript.

[yibeichan]

yes! we also encountered cases like SQL for a compute item...