[Fix/Gui] Change the string format operation for language - name.
This prevents a possible crash while formatting the lang-name string for presentation in the audio dialog.
Merge pull request #2790 from ace20022/lang_string

[Fix/Gui] Change the string format operation for language - name.
Remove broken usage of CSettingsCategory & CSettings
Use the new value of avi mime type in test
Clear file from cache in CDirectory::Remove()
Always set strnewDestFile to a value
Change to use IsWindowsVersionAtleast(..)