Detect worksheet ID in both old and new sheets.
Detect worksheet ID in both old and new sheets.

Tabletop.loadSheets looks at the ``data.feed.entry[i].link``
elements to determine the worksheet ID for each worksheet. With
old sheets, the worksheet ID can be parsed from the fourth link
element.  However, with new sheets, there are five entries in
``data.feed.entry[i].link``.

In either case, we can parse the worksheet ID from the last
element in ``data.feed.entry[i].link``.  So, use this last element
instead of hard-coding access to the fourth (index 3) element.

Faiz7412/tabletop,jsoma/tabletop,knmurphy/tabletop,muhanadra/tabletop,airtonix/tabletop,aendrew/tabletop,POWERWEBDESIGN/tabletop,aendrew/tabletop,AlmirKadric/tabletop,AlmirKadric/tabletop,AlmirKadric/tabletop,yiakwy/tabletop,greyhwndz/tabletop,jsoma/tabletop,greyhwndz/tabletop,POWERWEBDESIGN/tabletop,ohio813/tabletop,aendrew/tabletop,aendrew/tabletop,yiakwy/tabletop,jsoma/tabletop,yiakwy/tabletop,ohio813/tabletop,Faiz7412/tabletop,Faiz7412/tabletop,POWERWEBDESIGN/tabletop,knmurphy/tabletop,airtonix/tabletop,muhanadra/tabletop,POWERWEBDESIGN/tabletop,airtonix/tabletop,greyhwndz/tabletop,RachBLondon/tabletop,muhanadra/tabletop,yiakwy/tabletop,RachBLondon/tabletop,Faiz7412/tabletop,ohio813/tabletop,knmurphy/tabletop,knmurphy/tabletop,RachBLondon/tabletop