fix changing remotes in remotes dropdown

[zkxs]

When changing remotes using the dropdown in ungit 1.4.35, the following error occurs:

Firefox 64

TypeError: this.currentRemote is not a function[Learn More] remotes.js:97
    changeRemote remotes.js:97
    init/</< knockout:99
    dispatch jquery:5182
    add/elemData.handle jquery:4991

Chrome 69

Uncaught TypeError: this.currentRemote is not a function
    at Object.changeRemote (remotes.js:97)
    at HTMLAnchorElement.<anonymous> (knockout:99)
    at HTMLAnchorElement.dispatch (jquery:5183)
    at HTMLAnchorElement.elemData.handle (jquery:4991)

This issue prevents the user from changing remotes.

[zkxs]

@ylecuyer's suggestion looks good. I wasn't happy about outerThis so I'm glad to see it go.