BUG: 'cherry-pick -x' corner case

When cherry-picking a (presumably trivial) commit that has only the one-line summary (and no further text), cherry-pick -x appends it's message directly to the one-line summary.

Thereby creating a commit which has a two-line summary.

Aside from that, even with a non-trivial commit the generated note "(cherry picked from commit 555c9864971744abb558796aea28e12a1ac20839)" seems abrupt when appended directly.

I'd suggest:

"\n[cherry-picked from commit 555c9864971744abb558796aea28e12a1ac20839]"

or even better:

"\n[cherry-picked from commit 555c986]"

I'll turn this into an actual patch if there's a chance of it being incorporated.

- Eric