Searching: Transliterate non-ascii characters to remove accents

[sbrl]

We should transliterate source pages before inserting them into the index such that a search for bïll will hit both bill, bïll, and bïĺl.

We've got 2 options here:

• iconv: https://stackoverflow.com/a/3542748/1460422 - We don't currently use this module, so it would be another dependency.
• intl via transliterator_transliterate(): https://stackoverflow.com/a/16022459/1460422

We should make sure that we add a setting for this, as non-english pages may experience issues (e.g. russian / cyrillic) if we don't transliterate correctly.

[sbrl]

Looks like this answer has just what we need:

$literator = Transliterator::createFromRules(':: Any-Latin; :: Latin-ASCII; :: NFD; :: [:Nonspacing Mark:] Remove; :: Lower(); :: NFC;', Transliterator::FORWARD)

This not only removes diacritics, but also correctly handles cyrillic (and other alphabets too I assume).

[sbrl]

Looks like this answer has just what we need:

$literator = Transliterator::createFromRules(':: Any-Latin; :: Latin-ASCII; :: NFD; :: [:Nonspacing Mark:] Remove; :: Lower(); :: NFC;', Transliterator::FORWARD)

This not only removes diacritics, but also correctly handles cyrillic (and other alphabets too I assume).

[sbrl]

Done! :D