Some fixes (&->\&, _->\_) to remove latex complaints.

Some fixes (&->\&, _->\_) to remove latex complaints.

Actually the whole point of this excercise was to try to make a nice pdf file
with contents tree and thumbnail pages using pdflatex, but it keeps depleting
tex's resources :-(

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@5884 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775