Automatic language detection (Win Vista/7)

see issue 847

rtgui/multilangmgr.h

@@ -28,6 +28,8 @@ class MultiLangMgr {
     std::map<std::string, Glib::ustring> transTable;
     MultiLangMgr* fallBack;
     
+    Glib::ustring TranslateRFC2Language(Glib::ustring rfcName);
+
     public: 
 	MultiLangMgr () : fallBack (NULL) {}
 	MultiLangMgr (Glib::ustring fname) : fallBack (NULL) { load (fname); }
@@ -36,6 +38,9 @@ class MultiLangMgr {
         bool load (Glib::ustring fname, MultiLangMgr* fb = NULL);
 	bool save (Glib::ustring fname);
         
+    bool isOSLanguageDetectSupported();
+    Glib::ustring getOSUserLanguage();
+
         Glib::ustring getStr (std::string key);
 };