--format JSON shows all issues even when ran with -s dirty

I'm attempting to create .json file that shows which files has issues (to be used ... somewhere. Exactly where/how uncertain! =). My issue is that even though I run `watson -s dirty --format json`, the resulting `.watsonresults`-file has all files, with or without issues.

Second bit is a query: Would it be possible to change the name of the resulting file? I can easily move it, but ...
