riyadussalihin:14:9 --> https://sunnah.com/riyadussalihin/14/9

**Is your feature request related to a problem? Please describe.**
A new link type, `riyadussalihin:...`, to obtain Islamic narrations
and present them in English **or** in Arabic, according to a toggle.

**Describe the solution you'd like**
For example, `riyadussalihin:14:9|Arabic` yields the Arabic portion of
https://sunnah.com/riyadussalihin/14/9;
whereas `riyadussalihin:14:9` and `riyadussalihin:14:9|English`
both yield the English counterpart.

**Additional context**
It would be nice to refer to other narration texts and other religious texts.