Bug 17518: Displayed language name for Czech is wrong

Bug 17518: Displayed language name for Czech is wrong

It's "Ceština" and should be "Čeština"

Test plan:
1) apply the patch
1.1) update database
2) install Czech translation for Koha
3) note the language name in language switcher (in staff client and
    opac) is right: "Čeština"

Signed-off-by: radiuscz <radek.siman@centrum.cz>
Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
(cherry picked from commit de2ba75c25f9f348a312093483dea52168fa5d6e)
Signed-off-by: Frédéric Demians <f.demians@tamil.fr>
(cherry picked from commit 3ea0d7ed993a0c1233e822f7f4db710cb9056cfd)
Signed-off-by: Julian Maurice <julian.maurice@biblibre.com>