[keycloak-dev] Support UTF-8 encoding theme message properites

Hello all, I am trying to translate all base theme messages to my country language, Japanese. And I'd like to contribute them. Before that work, I'd like to propose about the files encoding. Currently, the message files (*.properties) are loaded with ISO-8859-1 encoding. Therefore, it is necessary to convert the files by 'native2ascii' command beforehand. However we can directly read the property files with UTF-8 encoding in java 1.6 or later because 'java.util.Properties#load(java.io.Reader)' method was introduced as below. http://docs.oracle.com/javase/6/docs/api/java/util/Properties.html#load(j... So, my proposal is supporting the message files with UTF-8 encoding. I believe that it's very developers/customers friendly. In addition, we can easily review the translated messages on the github pull request view and so on. What do you think? If it's ok, I'll create a JIRA issue and create a pull request. Regards, -- Hiroyuki Wada, Developer, Nomura Research Institute, Ltd.