Optional adding of two/three-letter language codes to names of downloaded subtitle files (#72, #108)

[a-sum-duma]

Related feature requests: #72, #108

Current implementation adds new option into the settings windows - "Add language code to subtitle file name". There are three choices:

• No
• Two-letter
• Three-letter

If user selects "Two-letter" or "Three-letter" then every time subtitles are downloaded, appropriate language code will be added to the name of subtitles file e.g. if "Three-letter" is selected and user downloads polish SRT subtitles for "movie.mkv" video file, the name of subtitles file will be "movie.pol.srt".

Also when batch-downloading subtitles ("Scan directories" window), if "skip video files which already have subtitles" option is selected, subtitles with language codes in file names will be recognized too.

The "Add language code to subtitle file name" option is common for both languages - the primary and the secondary. Some suggested that it could be separate, but I think there is no point in doing so. Balance between functionality and simplicity must be kept.

Similarly the "skip video files which already have subtitles" option don't care about the language of existing subtitles. The option could have more variants i.e. "skip only if the language is unspecified (no language code in file name) or primary". But again, less is better in this case IMO.

Let know what you think.

[lefti696]

@krzemin zerknij w MR