Updated i18next translations

* new el-GR, fr, nds, pt-BR
* updated de, en, es
bump grunt-text-replace to v0.4.0
Create own replace task for locales

Using regular expression to avoid unintentional replacements
Renamed Greek language file
Updated i18next translations

* updated german and french locales
Merge pull request #56 from Zauberstuhl/update_i18n_locales

Updated i18next translations