Document ntp multiple vulnerabilities.
Update 4.2.6p5 --> 4.2.8

Security:	VUXML: 4033d826-87dd-11e4-9079-3c970e169bc2
Security:	http://www.kb.cert.org/vuls/id/852879
Security:	CVE-2014-9293
Security	CVE-2014-9294
Security	CVE-2014-9295
Security	CVE-2014-9296
Forbid due to http://www.kb.cert.org/vuls/id/852879.

Security:	VUXML: 4033d826-87dd-11e4-9079-3c970e169bc2
Security:	http://www.kb.cert.org/vuls/id/852879
Security:	CVE-2014-9293
Security	CVE-2014-9294
Security	CVE-2014-9295
Security	CVE-2014-9296
- Update to version 1.212 and thus unbreak (unfortunately, upstream does not
  keep old versions on their site, at least not for long enough)
- Sanitize -COMMENT, simplify installation of documentation files
- Consistently reformat first two paragraphs of pkg-descr so it produces less
  ragged right edge
- Update to 1.24.1
Add security/nettle dependency and fix pkg-plist.
Squid detects libnettle when available and uses it without yet forcing
it as a required dependency.