adapt upgrade script to 3.5
migrate users to samba if required
dump ldif data before upgrade
fixed ldif dump and workarounds to continue failed upgrade
better retries workaround
added changelog entry
switch local debs-ppa when debugging
do initial-setup of samba at the end
Merge branch '3.4' into jacalvo/upgrade-to-3.5

Conflicts:
	main/core/ChangeLog
fixed development ppa url to avoid conflicts
stop apache2 to avoid conflict with haproxy
do apt-get clean before to reduce no disk space problems
start apache again after temporary stop
upgrade perl and haproxy first
enable upgrade UI
more visibility to removed packages warning
Merge branch 'jacalvo/upgrade-to-3.5' into 3.4