Moved unload/update in update thread

git-svn-id: http://devserv/svn/fluxdvd/components/wxPDFView/trunk@8156 ee4118f4-65c3-8c42-83c6-dbb17464b6b1
Restructured bookmarks to make other bookmarks controls easier

git-svn-id: http://devserv/svn/fluxdvd/components/wxPDFView/trunk@8159 ee4118f4-65c3-8c42-83c6-dbb17464b6b1