Merge pull request #8 from LaurentGoderre/add-language-output

Added locales output to enable pipping to other tasks
Merge pull request #7 from LaurentGoderre/use-default-on-missing

Added option to use the default locale for missing translations
Merge pull request #6 from LaurentGoderre/add-ext-option

Added option to customize the extensions
Allow to specify which worksheet to load translations from