(fixes #494) Ignore indent rules on files other than .vue

[michalsnik]

As pointed in #494 indent rules affects all files, thus script-indent lints not only .vue files, but also .js files.

I think that we should encourage usage of native eslint indent rule and script-indent only for single file components, where people might want the extra base indentation.

[mysticatea]

LGTM, but this is a breaking change we should write in the changelog.

[michalsnik]

We're still in beta phase @mysticatea and actually this change won't introduce more issues being reported, rather less - so it shouldn't break anything.

[mysticatea]

@michalsnik It's a surprising change to people which is using the rule for .js files as well. They will lose linting about indentation. It's the reason I said, "we should write in the changelog."

[chrisvfritz]

@mysticatea I agree it should definitely be included in the changelog! 🙂 But is reducing the scope of a rule typically considered a "breaking change" in ESLint? In this context, I was thinking of a breaking change as anything that could produce potentially undesired errors. I'm quite inexperienced in the ESLint community though, so maybe I've been thinking about it wrong. 😅