Change typo Localisation to Localization for Bug # 3102

Change typo Localisation to Localization for Bug # 3102

[RM note: I think there are a few people who wouldn't
 call "localisation" a typo - such as our UK, NZ,
 Australian, etc. contributors ;-) ].  That said,
 I'm pushing this patch to consistent with the
 general trend of the English varient used on the
 /prog/ templates.  There's no implication that en_US
 is the "correct" version of the language.]

Signed-off-by: Galen Charlton <galen.charlton@liblime.com>
Signed-off-by: Henri-Damien LAURENT <henridamien.laurent@biblibre.com>