Frank's patch https://github.com/zotero/zotero/issues/132
Menu item to swap creator first/last names (#132)
Merge 'gracile/fbennett-patch-authors'
Put "Swap first/last names" in creator context menu root

And remove "Transform Name Form" menu for now

Discussed in #132
Tweaks to name-swapping menu

- Don't show menu if item isn't editable
- Make DOM access more robust
- Fix whitespace
Merge branch 'swapCreatorNames' into 3.1

Closes #132, Menu item to swap creator first/last names
Closes #163, Frank's patch: Menu item to swap creator first/last names