Patch Set 3: I would prefer that you didn't submit this

(6 inline comments)

Looks quite good already.

After successfully storing the credentials I found that I used the wrong user name for my test repository on github. I didn't find a way to update the stored credentials for this repository. I think this is required.

As a workaround I deleted the secure store (unfortunately only the complete store can be deleted but not individual entries). After that I could not push anymore:

An internal error occurred during: "Push to HelloWorld - origin".
Preference node "null" has been removed.