Update reference prefix manager to the new version of adapters.
Added 4teamwork ldap configuration to ignore list.
Disable the reference prefix manager for administrators for the moment.
Merge pull request #122 from 4teamwork/lk_4tw_ldap_config

Added ldap configuration to manifest.in ignore list.
Merge pull request #120 from 4teamwork/lk_fix_reference_prefix_manager

Update reference prefix manager to the new version of adapters.
Merge pull request #121 from 4teamwork/pg_disable_reference_prefix_for_administrators

Disable the reference prefix manager for administrators for the moment.
Updated Changelog: added missing entries for the next release(3.1).
Preparing release 3.0.1

Conflicts:
	docs/HISTORY.txt
Merge pull request #123 from 4teamwork/pg_changelog_cleanup

Changelog cleanup
Preparing release 3.1
Back to development: 3.1.1
Fixed CleanupReferencePrefixMapping upgradestep

Works now for reference to no longer existing objects.
Merge pull request #124 from 4teamwork/pg_fix_cleanup_reference_prefix_upgradestep

Fixed CleanupReferencePrefixMapping upgradestep
Preparing release 3.1.1
Back to development: 3.1.2