avoid need for handling mapnik::config_error specifically to be robust against changes in headers upstream in mapnik

git-svn-id: http://svn.openstreetmap.org/applications/utils/tirex@29246 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
malloc.h is not available on osx and should not be needed to be explicitly included on other platforms

git-svn-id: http://svn.openstreetmap.org/applications/utils/tirex@29247 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4
fix mapnik-backend/renderd.cc compile against different mapnik and boost filesystem versions

git-svn-id: http://svn.openstreetmap.org/applications/utils/tirex@29248 b9d5c4c9-76e1-0310-9c85-f3177eceb1e4