Adapt content text to singular / plural forms

[Phyks]

Guidelines are meant to remain open issues, just for contributors information.

When one bike/stand is available, we should write "1 vélo disponible" instead of "1 vélos disponibles" (in bikes / stands view).

edit: by @eliemichel
I reopen this issue as a guideline. We need to keep in mind to take singular and plural forms into account.

[Phyks]

Closed by 5a1c1ee.

[eliemichel]

We might add a guideline to remember to care about that.
And I wonder how it interacts with i18n.

[Phyks]

We should do the same with i18n. Something like both a singular and plural form for every sentence / word.

👍 for the guideline.

[eliemichel]

I reopen this as a guideline