furigana-plain versions of handlebars

[YonKuma]

There are a couple Japanese card types right now that use a Sentence Furigana field that consists of the sentence with a bolded target word and Anki-style bracketed furigana (eg 今[いま]). Currently, those cards rely on Anki add-ons to accomplish this, but it would be nice if there were a way to generate this content natively from Yomitan, especially for users on devices that don't support add-ons.

I'm proposing the following handlebars:

• {sentence-furigana-plain}
• {cloze-prefix-furigana-plain}
• {cloze-body-furigana-plain}
• {cloze-suffix-furigana-plain}

They would function the same as their current cloze handlebars equivalent, but with added Anki-style furigana.