Add possibility to log all lint erros if the user use the shortcut

I find it useful to have the possibility to display all errors and click on the error to go to the correct line/col.

I implement this feature and it works only when you are using the linter shortcut (because I also want to keep the old behavior).

![atomlinter](https://cloud.githubusercontent.com/assets/1850538/3978589/c5444108-2849-11e4-8b64-5508f24c61a6.gif)

I would like to know if you find this feature useful.

If so, I still have some works to do on this PR:
  - Adding specs
  - I don't like the way how I get the line number/col of the error. Need to think about a better solution.

I still think it's unexpected to click the error, then have 2 completely independent things happen. Nobody will be expecting that and I think the experience is made worse in both directions:

 * Users trying to navigate to the error will wonder why their clipboard was blown away
 * Users trying to copy the error message will wonder why their window jumped around

I think you need to separate these two things into 2 different actions.