Remove WWW entries moved into port Makefiles
Commit b7f05445c00f has added WWW entries to port Makefiles based on
WWW: lines in pkg-descr files.
This commit removes the WWW: lines of moved-over URLs from these
Approved by: portmgr (tcberner)
Add new ports biology/plink  and biology/plinkseq :
PLINK is a free, open-source whole genome association analysis toolset.
PLINK/SEQ is an open-source C/C++ library for working with human
genetic variation data.
PR: ports/171918 
PR: ports/171922 
Submitted by: Jason Bacon <jwbacon at tds.net>