Major update to the pc-updatemanager utility.

Change how we perform updates to new "major" releases of Free/PC-BSD

Now, instead of relying on the always failing pkgng upgrade system, use
the pc-updatemanager to build lists of the old system pbis/pkgs/metapkgs
, install the new world / kernel and then re-install the PBIs / metapkgs.

As a bonus, we will now keep these lists, and generate a summary file which
can be used post-install to diagnose any potential problems during the upgrade.

I still need to finish some additional parsing to grab any user-installed pkgng
apps.
Auto-Commit of i18n data from Pootle
Enable 'Exit' menu; Capitalize 'C' letter in 'Update Center' words in window caption, menu entry and control pane item. closes #904
Fix a couple of bugs doing ZFS restores when using SSH with a password
Merge branch 'master' of github.com:pcbsd/pcbsd
Finish cleaning up the new system manager ports/source checkout functionality.
Also create a backend class that just contains a bunch of static functions for simple usage elsewhere (like generating ports update commands). This will make it easy to update the utility later if URL's or other system calls change (since we don't need to worry about all the GUI-specific stuff getting mixed in).
Merge branch 'master' of github.com:pcbsd/pcbsd
Add a new 'pkgdeps' target to pc-metapkgmanager, it will allow listing
the pkgng packages that a meta-package will install
Clean up a lot of the built-up kruft in the main system manager UI from the very old days.
Merge branch 'master' of github.com:pcbsd/pcbsd
Fix a bug pulling the correct LP props file from a remote host
Merge branch 'master' of github.com:pcbsd/pcbsd
Small update to wrapper scripts, add special flag which indicates if
newer wrapper is passing along the cwd to pbime
Add a bit of debugging to the PCDM keyboard layout switcher.
Merge branch 'master' of github.com:pcbsd/pcbsd
Latest version of 10 Guide draft
Large update to the PCDM keyboard layout switcher:
*Fix detection of current keyboard settings
*Make sure that system settings are not changed unless "apply" is clicked
*Make sure that keyboard variants are being detected/available properly.
*Fix a logic bug preventing the keyboard from being changed outside the GUI
Merge branch 'master' of github.com:pcbsd/pcbsd