* Fix aspect ratio when scaling small images, and add support for
converting SVG and PDF graphics to PNG.
Thanks, chrysn
+ - suggest ghostscript (required for PDF-to-PNG thumbnailing)
+ and libmagickcore-extra (required for SVG-to-PNG thumbnailing)
+ - build-depend on ghostscript so the test for scalable images can be run
* In the CGI wrapper, incorporate $config{ENV} into the environment
before executing Perl code, so that PERL5LIB can point to a
non-system-wide installation of IkiWiki.