* Add iCheck png files to webpack config (inconsistency for css <> png) and blue.png to public folder
* php 7.3 collect() fix (undefined variable)
* Fix travis ci
* Add iCheck png files to webpack config (inconsistency for css <> png) and blue.png to public folder
* php 7.3 collect() fix (undefined variable)
* change LDAP implementation from model to (singleton) service
* Re-apply check for content in ldap_server variable before parsing
* Update LDAP implementation
* Switch iCheck to minimal as referenced in js
* Don't init on load but on first access via init (returns ldap enabled status)
* Re-Enable notifications
* Re-add missing test target php versions
* Only init() once (singleton class, so ldap variable is already set)
