Tags are not passed to cucumber correctly

[tomhicks-bsf]

According to this article, the way pioneer passes its tags to cucumber is totally wrong when there are multiple tags.

If I set my tags to ["@one", "@two"] pioneer passes them as --tags=@one, @two which is not any of the supported tag formats. Arguably, that should come out as --tags=@one --tags=@two, which would then allow us to do proper AND/OR combinations:

["@this,@that", "~@skip"] -> --tags @this,@that --tags ~@skip -> (this OR that) AND NOT skip