Rules for whitespace in Pyret strings are ignored when displayed in an SVG

[schanzer]

If a reactor displays an SVG element (as is the case for literally every chart) and the SVG element has a TEXT element within it, that string will be displayed using the browser's default whitespace-collapsing behavior.

This is a problem for charts of ours that include a lot of data in their titles:

We'd like to separate those strings, but adding spaces between them in Pyret doesn't help because of this issue.