Add a patch fixing a long-standing security problem. Bump PORTREVISION.

PR: 196351
Differential Revision: D1593
Submitted by: Jan Beich
Security: https://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2012-6129

While here, arrange for building a few of the small utilities bundled
with library, and install them along with another potentially useful
header-file.

Sponsored by: http://libpipe.com/