[CTF] pkg 1.6.0

Hi all,

We are about to release pkg 1.6.0. pkg-devel has been updated to 1.5.99.13 aka
1.6.0 rc3 that we hope will become the new pkg 1.6.0 btw the end of the Week
(release planned for Saturday 26th of September or no important issues are
raised)

On the list of changes:
- Lots of improvements in the solver (in particular fixes the case like the
  recent jpeg upgrade)
- Lots of fixes in the 3 way merge code
- pkg add can now work without a version specified in the dependency line
- pkg check -d now also check the required libraries
- Improved support for partial upgrades
- Improved zsh completion support
- Improved linux support (now all regression tests passes on linux)
- Messages can now be context aware: (only print a given message during
  installation, upgrade - version aware -, removal, or always)
- _at_keywords now accepts new entries to add context aware messages
- Add the ability to generate graphiz's dot format representation of the
  solver's problem
- pkg search now default on showing the comments of of the matched packages
- Lots of bug fixes and code cleanup
- Plenty of new bugs

Please test heavily, I would like to make a release quite soon to limit the
number of users suffering from the jpeg->jpeg-turbo update.

Best regards,
Bapt