Fixed incorrect plural form in header....

It seems like french plural form looks like this:
"Plural-Forms: nplurals=2; plural=(n==1? 0 : 1);\n"
But the correct value is:
"Plural-Forms: nplurals=2; plural=(n > 1);\n"

http://localization-guide.readthedocs.org/en/latest/l10n/pluralforms.html