Reduce white space in the PDF version of the Guide

[geealbers]

Claire pointed out that there's an excessive amount of white space in the Guide and that it's breaking up its readability. She's fine if the images don't appear with the entries, but obviously that would mean rearranging things in the online version as well. @egardner, can you try making the images smaller and seeing if that helps the flow? Or if there are a few key spots that are causing the bulk of the trouble, perhaps we do need to rearrange?

[egardner]

Okay, here's a somewhat improved version of that section.
test.pdf

[ruthlane]

That looks much improved. FYI, before you spend too much time on the Guide layout—Claire wants to add dimensions to the captions, so that may add a line or four (in the case of fig. 5).

[egardner]

Made some more improvements as of d5a09cf, the whole Campania image section now appears as a grid since they outrun the text otherwise.

[geealbers]

As of e015493, we've got Clarie's okay and can close issue