Move language splitting logic from analyse() to makeTranslationReady()

Although the SVG spec supports multi-language text tags (e.g. "en,fr,de")
these are a really poor idea since (a) they are confusing to read and
(b) the desired translations could diverge at any point. So get rid at
the earliest possible juncture, i.e. in makeTranslationReady().

Fix associated tests that relied on order of <text> elements.

Change-Id: I9a0aa022315e38e7cb7eae0563d05cf4837de637