added support default localized mail templates
Merge pull request #121 from globaleaks/feature/localized_mails_templates_inclusion

added support default localized mail templates
addressed issue https://github.com/globaleaks/GlobaLeaks/issues/926
minor refactor related to links including :lang argument
Merge pull request #122 from globaleaks/feature/localized_wizard

addressed issue https://github.com/globaleaks/GlobaLeaks/issues/926
addressed issue https://github.com/globaleaks/GlobaLeaks/issues/943