Translating labels and default texts

I am trying to change the editor interface for h5p.DragnQUestion library to Turkish, but I couldn't fix that. I have used the http://h5p.org/node/581 tutorial and added a tr.json file /sites/default/files/h5p/libraries/H5P.DragQuestion-1.0/language/tr.json but still it didn't effect the display. I have also tried to change /sites/default/files/h5p/libraries/H5P.DragQuestion-1.0/semantic.json and changed english labels with Turkish translates yet it didn't affect the display also. I have cleared cache everytime btw. Still it doesn't affect. I think there is some thing cahcing the old semantic.json or am I changing the wrong files? I need this drag and drop question interface to be translated and actually not using i18n module on my drupal site. Dunno if I should install that module , I have set up all the links page urls and this module will add /tr to the url so this will break a lot of content. Is there a way to change core files in such a way to translate english labels into Turkish. Excluding the updateing the module problem, how can ı change the albes into Turkish?  In short, the changes I made in semantics.json file doest affect the display. I have checked devel tab and saw json_content is same and din't changed yet my semantic.json file already modified. I am sure this is not a big work but I just couldn't figure out how to change those labels and texts inside editor. 

I have checked database and saw the language files are stored there but still those language files are callaed if I sue i18n or some translation module, isn't it? If possible, I don't want to use a translation module in first , and wanan change the hardcoded labels if possible. 

Please I need immediate help. Thanks for the module btw, it is amazing and saved me a lot of time.