[l10n] Enable 15 years template for new locales (cs, it, ms)

cs: Bug 868966
Added email address and localized banner, inserted in LOCALES_WITH_MOZ15.

it: Bug 884248
Added email address and localized banner, inserted in LOCALES_WITH_MOZ15. 
CSS fix for slide 10.

ms: Bug 885975
Added email address, inserted in LOCALES_WITH_MOZ15, they're using the same banner currently used by "id" (so no new image, just css rule).

ta:
Fixed wrong bottom padding for slide 10 (total top+bottom 46px instead of 56px. the background is slightly cut).