add svg icon defs only if it gets referenced by any port
change feature tags
markup uris as attributes
always use generic gui. annotate screenshot with plugin uri.
adapt to new output of lv2xinfo (uris as attributes), show features, misc, rough clenaup (still needs more)
place screenshot inside data tag. give uri and type (1=generic, 2=custom)
adapt to use lv2plugin/@uri
output formatting
update examples