Fix string fields sorting

[shekhirin]

Resolves #333

curl checks

➜  ~ curl -s 'localhost:7700/indexes/movies/search' -d '{"sort": ["title:asc"], "limit": 30}' | jq -r '.hits | map(.title)[]'
#1 Cheerleader Camp
#Horror
#RealityHigh
#Roxy
#SquadGoals
$5 a Day
$9.99
'71
(2)
(500) Days of Summer
(Girl)Friend
*batteries not included
...And God Created Woman
...And Justice for All
...E fuori nevica!
.45
1
1 Mile To You
1 Night
10
10 Cloverfield Lane
10 giorni senza mamma
10 Items or Less
10 Rillington Place
10 Rules for Sleeping Around
10 Things I Hate About You
10 to Midnight
10 Years
10,000 BC
10,000 Saints

➜  ~ curl -s 'localhost:7700/indexes/movies/search' -d '{"sort": ["title:desc"], "limit": 30}' | jq -r '.hits | map(.title)[]'
크게 될 놈
왓칭
뷰티플 마인드
노무현과 바보들
ハニー
Счастье – это… Часть 2
СОТКА
Смотри мою любовь
Позивний 'Бандерас'
Лошо момиче
Күлүк Хомус
Куда течет море
Каникулы президента
Ακίνητο Ποτάμι
Üç Harfliler: Beddua
È nata una Star?
Æon Flux
Ága
À propos de Nice
À Nos Amours
À l'aventure
¡Three Amigos!
Zulu Dawn
Zulu
Zulu
Zu: Warriors from the Magic Mountain
Zu Warriors
Zorro
Zorba the Greek
Zootopia

[curquiza]

Thanks for your PR ❤️
Kero will review it as soon as possible

[Kerollmops]

Apart from the fact that we use rand::thread_rng() which isn't seeded and therefore not easily reproducible, I like your fix. I forgot about this loop thing that I have done in the FacetNumberRevRange iterator and the reverse one only.

Thank you very much for your help again @shekhirin, merging ⚗️
bors merge

[bors]

Build succeeded:

• Run Rustfmt
• Tests on macos-latest with stable
• Tests on ubuntu-18.04 with stable
• Tests on windows-latest with stable