#5 Add polish/german/canadian language files

[romg]

To add a language a file, use /ressources/lang/message.properties as template
For naming, refer to ISO639, ISO3166 and http://java.sun.com/developer/technicalArticles/Intl/IntlIntro/
Example:
generic french language file message_fr.properties
french language file for french people message_fr_FR.properties
french language file for canadian people message_fr_CA.properties