Remove --summary from man page
Remove --summary from man page

This option has been deprecated by --metadata-file and removed.

Fixes #325

willscott/zmap,zmap/zmap,willscott/zmap,shakenetwork/zmap,shakenetwork/zmap,shakenetwork/zmap,willscott/zmap,willscott/zmap,zmap/zmap,zmap/zmap,willscott/zmap,shakenetwork/zmap,shakenetwork/zmap