ports/131821: Update port: graphics/pngwriter to 0.5.4

[miwi at FreeBSD.org]

Synopsis: Update port: graphics/pngwriter to 0.5.4

Responsible-Changed-From-To: freebsd-ports-bugs->miwi
Responsible-Changed-By: miwi
Responsible-Changed-When: Wed Feb 18 18:02:13 UTC 2009
Responsible-Changed-Why: 
I'll take it.

http://www.freebsd.org/cgi/query-pr.cgi?pr=131821