- Mk/bsd.database.mk rewrite, new default to db5.
- db6 is eligible by default only if installed on the system.
- Bump PORTREVISION of all ports that directly depend on BerkeleyDB or
  where USE_BDB is found in the port's directory
- Patch a few ports such that they will pick up or work with newer
  versions.
- Add UPDATING entry
- Drive-by format fix for pks
- Drop BerkeleyDB option from mail/popular for now, requires more work.
- Exp-run logs linked from the PR below.
- Ports that do not build (IGNORE, BROKEN, etc.) have pro-forma changes
  for new Berkeley DB, but are untested.

NOTE: please read UPDATING and the Wiki page before proceeding!

Announcement:	http://lists.freebsd.org/pipermail/freebsd-ports-announce/2014-August/000090.html
Wiki reference:	https://wiki.freebsd.org/Ports/BerkeleyDBCleanup
PR:		192690
Approved by:	portmgr (implicit, PORTREVISION bump on unstaged ports)