New cronk list style, icon style still selectable

CSS styles updated
CronkListingPanel updated to allow switching (with states)
added config option org.icinga.cronk.liststyle (list|icon)

(refs #3396)
Removed cronk menu background (refs #3430)
Removing authid requirement from LDAP Auth

The LDAP Module relayed in many parts on the correct content of "authid", which held the full DN of a user inside LDAP.

This will be changed to work with the default filters and settings specified in the XML configuration.

A admin should make sure that if multiple LDAP trees are used no overlapping in terms of the usernames exists.
(refs #3473)
Nested filter working stage
Merge branch 'master' of ssh://git.icinga.org/icinga-web
Prepare for 1.8.1
exceptions/logging: Fix "PHP Fatal error:  Cannot redeclare printPlainMessage()..."
Added improved filter tree, added possibilty to join one field muultiple times (e.g. for selecting multiple customvars)
exceptions/logging: Fix "Uncaught AppKitPHPError: PHP Error ob_end_clean(): failed to delete buffer. No buffer to delete..."
Filter fixes, jsint fixes
* removed cronk_filter reference in models
Filter bugfixes
Remove native state

This state handles auto added columns and not existing
ones from templates, refs #3431
Cronk format compat

Old 1.6 is detected not and can be displayed
in filter manager
Merge branch 'mhein/custom-cronks-3431'
Merge branch 'mhein/fixes'
Merge branch 'master' of ssh://git.icinga.org/icinga-web into jmosshammer/filtering

Conflicts:
	configure
	etc/make/version.m4
Credentials and Properties are now cached in the session storage
lease enter the commit message for your changes. Lines starting
Merge branch 'jmosshammer/performance' of ssh://git.icinga.org/icinga-web into jmosshammer/filtering
Better icon for filter conjunctions