i18n: add Czech translation (#64)

Author: jcek3

src/i18n/Engine.cpp

@@ -10,6 +10,9 @@ void I18n::initEngine() {
     // ar (Arabic)
     engine.registerEntry("ar", TXT_KEY_SEARCH_SOMETHING, "بحث...");
 
+    // cs_CZ (Czech)
+    engine.registerEntry("cs_CZ", TXT_KEY_SEARCH_SOMETHING, "Hledat...");
+    
     // da_DK (Danish)
     engine.registerEntry("da_DK", TXT_KEY_SEARCH_SOMETHING, "Søg...");