Made some changes (i18n localize)

cc8bff8a86
added "de" translation
using with google translate


54bf64e3b1
added uniq username control 
checked for duplicated user name pre on save


1a4b157cd9 
adding i18n support and localize datetime 
* adding multi lang support
* translated to turkish and english
* added momentjs for localized timestamp (lang and time formats)