cursor:pointer and link underline styling on headings misleading

[patrickhlauke]

following on from #54 i'd actually say that having the cursor:pointer and the apparent link underlining styling even on headings that do have the anchor/link functionality is misleading...it makes it appear like the whole heading is clickable, when in fact only clicking on the link icon on the left actually works.

[patrickhlauke]

while #73 addressed the cursor:pointer, this still leaves the underline on the whole of the heading (while only the icon on the left is clickable). debatable if this should also be removed / changed so that it only shows the whole heading underlined when that icon itself is hovered (if that's feasible, probably with sibling selectors)