Bug 6361 - make the packages work with koha 3.4

Bug 6361 - make the packages work with koha 3.4

This commit does the following:
* Merge the changelog from the releases of 3.2
* Adds a command 'koha-upgrade-to-3.4' that does the MARC item splitting
  stuff.
* Adds a debconf note to make sure people know that they need to run
  the above command.
* Fixes the inclusion of jQuery in the packages.
* Makes build-git-snapshot build packages with a 3.5 version.

Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>