Enhancement: offer push to remote rather than configuring remote

[randy3k]

Close #738
when creating PR without tracking remote, prompt to push to remote instead of asking to configure remote tracking branch.

PS: this PR is created by this feature.

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• 2017-08-15T19:57:27.781Z:05000fc: The pull request was created
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[stoivo]

What is the benefit of using WindowCommand instead of TextCommand, performance?

[randy3k]

We don't need any view to invoke these commands.

[randy3k]

Thanks @stoivo

[sheldon]

Thanks for the really quick implementation, this does exactly what I had in mind :)