Add setting to selectively autosave based on grammar/scope

[henri-hulski]

I'm using the git-plus package and autosave is enabled.
When I want to commit and I wait to long while composing the commit message, the commit message get autosaved and the commit fired before I finished.

Maybe there should be a setting to blacklist files, which should not be autosaved.

[aki77]

I have the same problem.
I implemented package.
https://atom.io/packages/autosave-plus

[henri-hulski]

Sounds good. I will try it out.

[nineway]

This is already fixed in the Service API section in readme.md. #45

[50Wliu]

Thanks @nineway. Packages can implement this using the provided service.